Search

Objective: To investigate the effects of 12-week weight-bearing dance aerobics (WBDA) on muscle morphology, strength and functional fitness in older women. Methods: This controlled study recruited 37 female participants (66.31y ± 3.83) and divided them into intervention and control groups according to willingness. The intervention group received 90-min WBDA thrice a week for 12 weeks, while the control group maintained normal activities. The groups were then compared by measuring muscle thickness, fiber length and pennation angle by ultrasound, muscle strength using an isokinetic multi-joint module and functional fitness, such as 2-min step test, 30-s chair stand, chair sit-and-reach, TUG and single-legged closed-eyed standing test. The morphology, strength, and functional fitness were compared using ANCOVA or Mann-Whitney U test to study the effects of 12 weeks WBDA. Results: Among all recruited participants, 33 completed all tests. After 12 weeks, the thickness of the vastus intermedius (F = 17.85, P < 0.01) and quadriceps (F = 15.62, P < 0.01) was significantly increased in the intervention group compared to the control group, along with a significant increase in the torque/weight of the knee flexor muscles (F = 4.47, P = 0.04). Similarly, the intervention group revealed a significant improvement in the single-legged closed-eyed standing test (z = −2.16, P = 0.03) compared to the control group. Conclusion: The study concluded that compared to the non-exercising control group, 12-week WBDA was shown to thicken vastus intermedius, increase muscle strength, and improve physical function in older women. In addition, this study provides a reference exercise program for older women. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of 12-week weight-bearing dance aerobics (WBDA) on muscle morphology, strength and functional fitness in older women. Methods This controlled study recruited 37 female participants (66.31y ± 3.83) and divided them into intervention and control groups according to willingness. The intervention group received 90-min WBDA thrice a week for 12 weeks, while the control group maintained normal activities. The groups were then compared by measuring muscle thickness, fiber length and pennation angle by ultrasound, muscle strength using an isokinetic multi-joint module and functional fitness, such as 2-min step test, 30-s chair stand, chair sit-and-reach, TUG and single-legged closed-eyed standing test. The morphology, strength, and functional fitness were compared using ANCOVA or Mann-Whitney U test to study the effects of 12 weeks WBDA. Results Among all recruited participants, 33 completed all tests. After 12 weeks, the thickness of the vastus intermedius (F = 17.85, P < 0.01) and quadriceps (F = 15.62, P < 0.01) was significantly increased in the intervention group compared to the control group, along with a significant increase in the torque/weight of the knee flexor muscles (F = 4.47, P = 0.04). Similarly, the intervention group revealed a significant improvement in the single-legged closed-eyed standing test (z = −2.16, P = 0.03) compared to the control group. Conclusion The study concluded that compared to the non-exercising control group, 12-week WBDA was shown to thicken vastus intermedius, increase muscle strength, and improve physical function in older women. In addition, this study provides a reference exercise program for older women.

Objective: Previous work has outlined cognitive beliefs about exercise in general, but very little is known about momentary cognitions while engaging in pathological exercise. The primary aim of this study was to explore thought content during exercise and to test whether these thoughts predicted later engagement in eating disorder behaviors. We also tested associations between thoughts and specific exercise activity. Method: We monitored 31 women with clinically significant eating psychopathology for 3 weeks via ecological momentary assessment as they reported on their exercise and eating disorder behaviors, and thoughts about shape, weight, or calories during exercise. Thoughts were self‐reported upon cessation of each exercise session. Results: Thinking about weight loss during exercise predicted later engagement in body‐checking behaviors. Weight‐bearing exercise was associated with a decreased likelihood of thinking about calories but an increased likelihood of thinking about shape during exercise. Discussion: These findings show that shape and weight thoughts are present during exercise and that their influence on eating disorder behaviors may exist on a much briefer time scale (i.e., within a day) than previous studies show. Clinically, future studies may seek to test interventions aimed at changing or restructuring cognitions during exercise to help shape adaptive exercise behavior during and after treatment. Public Significance: This is the first study measuring thoughts during pathological exercise in real‐time among those with eating disorder psychopathology. The results show that thinking about weight loss during exercise might increase the likelihood of engaging in body‐checking behaviors. Findings will inform the development of treatment approaches to help those in recovery from eating disorders re‐engage with exercise. [ABSTRACT FROM AUTHOR]

Context: Unstable devices in various forms are used as therapeutic adjuncts for prevention or following an injury. A slip-over-the-shoe design with inflatable domes (STEPRIGHT® Stability Trainer) was developed to improve balance. It is unknown how this unstable device affects muscle activity during a closed-chain exercise such as the forward lunge. Objective: To compare muscle activity across 3 surfaces (STEPRIGHT®, Both Sides Up [BOSU®] Balance Trainer, and firm) during a forward lunge. Design: Within-subject, repeated measures. Setting: University physical therapy research laboratory. Participants: A total of 20 healthy, recreationally active subjects (23.4 [1.47] y, 172.7 [14.7] cm, 71.6 [16.8] kg). Intervention: Each subject performed 1 set of 10 repetitions of forward lunge exercise in random order with STEPRIGHT®, BOSU®, and firm surface. Main Outcome Measures: Surface electromyography data, normalized to maximum voluntary isometric contractions (%MVIC), was used to assess muscle activity on rectus femoris, vastus medialis oblique (VMO), biceps femoris, lateral gastrocnemius, fibularis longus, and tibialis anterior. Results: The repeated-measures analysis of variance determined that there was a significant effect for surface type. During the descent of the lunge, the STEPRIGHT® elicited higher rectus femoris (33% [27%] MVIC) compared with BOSU® (22% [14%] MVIC) and VMO (44% [15%] MVIC) on STEPRIGHT® compared with firm (38% [11%] MVIC) (P <.05). During the ascent of the lunge, the rectus femoris (38% [27%] MVIC) using STEPRIGHT® was higher than BOSU® (24% [16%] MVIC), and STEPRIGHT® elicited higher VMO (65% [20%] MVIC) versus BOSU® (56% [19%] MVIC) (P ≤.01). The STEPRIGHT® for fibularis longus was higher (descent: 51% [20%] MVIC, ascent: 52% [22%] MVIC) than BOSU® (descent: 36% [15%] MVIC, ascent: 33% [16%] MVIC) or firm (descent: 33% [12%] MVIC, ascent: 35% [15%] MVIC) (P <.001). Conclusions: Clinicians may choose to use the STEPRIGHT® for strengthening VMO and fibularis longus muscles, as these were over 41% MVIC or any of the 3 surfaces for endurance training (<25% MVIC) for biceps femoris muscle. This information may be helpful in exercise dosage for forward lunges when using STEPRIGHT®, BOSU®, or a firm surface. [ABSTRACT FROM AUTHOR]

PURPOSE This study aimed to determine the effects of weight-bearing exercise on health-related physical fitness and sleep index in pre- and postmenopausal women. METHODS Twenty middle-aged women were randomly assigned to premenopausal women (PRW; n=11) and postmenopausal women (POW; n=9) groups. All subjects engaged in weight-bearing exercises for 50 minute twice a week for 8 weeks. All participants underwent weight, body mass index (BMI), muscle mass (MM), body fat mass, body fat percentage, waist to hip ratio, bench press (BP), leg press (LP), 3-minute step test (3 MST), sit and reach test (SRT), air squat (AS), push up (PU), curl up (CU), grip strength (GS), and the Korean version of the Pittsburgh Sleep Quality Index (K-PSQI) measurements before and 4 and 8 weeks after the weight-bearing exercise program. RESULTS AS and PU improved significantly in the PRW versus POW group (p

Background: Although regular physical activity and exercise programs might improve bone health caused by oncological treatment and the disease itself, it remains unknown the pooled effect of exercise interventions following frequency, intensity, time and type prescriptions.Objective: This systematic review and meta-analysis aimed to synthesise evidence regarding the effectiveness of exercise interventions on bone health in children and adolescents with cancer during and after oncological treatment.Methods: A systematic search was conducted in the MEDLINE (via PubMed), Web of Science and Scopus databases from November 2021 to January 2022. Randomised controlled trials (RCTs) and non-RCTs reporting pre-post changes of the effectiveness of exercise interventions on DXA-measured bone parameters in young population (1–19 years) during or after oncological treatment were included. Pooled (ESs) and 95% confidence intervals (95%CIs) were calculated. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.Results: A total of eight trials with 341 participants were included. The meta-analyses did not reveal a statistically significant increase in whole body areal bone mineral density (ES = 0.10; 95%CI: −0.14, 0.34), lumbar spine (ES = 0.03; 95%CI: −0.21, 0.26) or femoral neck (ES = 0.10; 95%CI: −0.37, 0.56). Similarly, during the oncological treatment phase the ES was 0.04 (95%CI: −0.17, 0.25) and after the ES was 0.07 (95%CI: −0.20, 0.33).Conclusion: To date, exercise interventions have been inappropriate and therefore, ineffective to illustrate any beneficial effect on bone health in children and adolescents with cancer during and after oncological treatment.Systematic Review Registration: PROSPERO registration number: CRD42022310876

This study examined the low-impact dance intervention on the markers of bone metabolism, cognitive function, and functional fitness of postmenopausal women. Senior women were randomized into low-impact dance (LG) or control group (CG). Three dance sessions weekly were scheduled in the LG for 16 weeks. The markers of bone metabolism, bone composition, Stroop test, and functional fitness were assessed at pre- and post-intervention. The marker of bone formation, some of cognitive function and functional fitness were improved in the LG. The low-impact dance intervention benefited the marker of bone formation, parts of cognitive function and functional fitness. [ABSTRACT FROM AUTHOR]

Squatting has received considerable attention in sports and is commonly utilized in daily activities. Knowledge of the squatting biomechanics in terms of its speed and depth may enhance exercise selection when targeting for sport-specific performance improvement and injury avoidance. Nonetheless, these perspectives have not been consistently reported. Hence, this preliminary study intends to quantify the kinematics, kinetics, and energetics in squat with different depths and speeds among healthy young adults with different physical activity levels; i.e., between active and sedentary groups. Twenty participants were administered to squat at varying depths (deep, normal, and half) and speeds (fast, normal, and slow). Motion-capture system and force plates were employed to acquire motion trajectories and ground reaction force. Joint moment was obtained via inverse dynamics, while power was derived as a product of moment and angular velocity. Higher speeds and deeper squats greatly influence higher joint moments and powers at the hip (p < 0. 0 5) and knee (p < 0. 0 5) than ankle, signifying these joints as the prime movers with knee as the predominant contributor. These preliminary findings show that the knee-strategy and hip-strategy were employed in compensating speed and depth manipulations during squatting. In certain contexts, appreciating these findings may provide clinically relevant implications, from the performance and injury avoidance viewpoint, which will ameliorate the physical activity level of practitioners. [ABSTRACT FROM AUTHOR]

Abstract Background Exercise, especially weight-bearing exercise (e.g. walking), may affect plantar tissue viability due to prolonged repetitive high vertical and high shear pressure stimulus on the plantar tissue, and further induce development of diabetic foot ulcers (DFUs). This study aimed to investigate the effects of different accumulated pressure-time integral (APTI) stimuli induced by walking on plantar skin blood flow (SBF) responses in people with diabetes mellitus (DM). Methods A repeated measures design was used in this study. Two walking protocols (low APTI (73,000 kPa·s) and high APTI (73,000 × 1.5 kPa·s)) were randomly assigned to ten people with DM and twenty people without DM. The ratio of SBF measured by laser Doppler flowmetry after walking to that before (normalized SBF) was used to express the SBF responses. Results After low APTI, plantar SBF of people with DM showed a similar response to people without DM (P = 0.91). However, after high APTI, people with DM had a significantly lower plantar SBF compared to people without DM (P

Purpose: To examine differences between ground-reaction-force (GRF)-based parameters collected from 5 types of plyometric push-ups. Between-trials reliability and the relationships between parameters were also assessed. Methods: Thirty-seven highly active commando soldiers performed 3 trials of 5 variations of the plyometric push-up in a counterbalanced order: standard countermovement push-up (SCPu), standard squat push-up (SSPu), kneeling countermovement push-up (KCPu), kneeling squat push-up (KSPu), and drop-fall push-up (DFPu). Vertical GRF was measured during these exercises using a portable Kistler force plate. The GRF applied by the hands in the starting position (initial force supported), peak GRF and rate of force development during takeoff, flight time, impact force, and rate of force development impact on landing were determined. Results: During standard-position exercises (SCPu and SSPu) the initial force supported and impact force were higher (P < .001) than with kneeling exercises (KCPu, KSPu, and DFPu). The peak GRF and rate of force development during takeoff were higher (P < .001) in the countermovement push-up exercises ([CMP] SCPu, KCPu, and DFPu) than squat push-up exercises ([SP] SSPu and KSPu). Furthermore, the flight time was greater (P < .001) during kneeling exercises than during standard-position exercises. A significant relationship (P < .01) between impact force and the rate of force development impact was observed for CMP and SP exercises (r = .83 and r = .62, respectively). The initial force supported was also negatively related (P < .01) to the flight time for both CMP and SP (r = -.74 and r = -.80, respectively). It was revealed that the initial force supported and the peak GRF during takeoff had excellent reliability; however, other parameters had poor absolute reliability. Conclusions: It is possible to adjust the intensity of plyometric push-up exercises and train athletes' muscle power by correctly interpreting GRF-based parameters. However, caution is required as some parameters had marginal absolute reliability. [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the acute response of biochemical bone turnover markers (BTM) to high-impact jumping exercise, and to quantify the ground reaction forces (GRF) achieved during each jumping exercise, in postmenopausal women. In a randomized controlled cross-over study over three days, 29 postmenopausal women (age (mean±SD): 60.0±5.6 years) were randomly assigned to 6 x 10 repetitions of three different jumps: countermovement jump (CMJ), drop jump (DJ), diagonal drop jump (DDJ). A fourth day without jumping served as a control (CON). Blood samples were collected before (PRE), after (POST), and 2 hours after (2Hr) exercise. Bone turnover was evaluated by bone formation markers (procollagen type-1 aminoterminal propeptide (P1NP) and osteocalcin (OC)) and the bone resorption marker C-terminal telopeptide of type-1 collagen (CTX). Peak anteroposterior (Fx), mediolateral (Fy), and vertical (Fz) GRF were measured using a force platform. From PRE to POST, P1NP increased (p

Objective: To discuss the effects and function of LIPUS on muscle atrophy (MA), analysis from various aspects through the study of low-intensity pulsed ultrasound (LIPUS) information technology intervention (ITI) in diagnosis and the prediction of muscle atrophy. Method: In this study conducted in our university, 74 healthy female SD rats aged three months, weighing 100-200g were selected. All rats were placed in sterile cages from June 2020 to September 2020. They were divided into three groups. In the OVO group and OVE group, the mice are treated with LIPUS, Finally, the changes of body weight, grasping power, biochemical indexes and glycogen content of gastrocnemius muscle were analyzed and recorded to explore the effect and value of LIPUS ITI combined with intermittent weight-bearing exercise in the treatment of MA Results: After weight-bearing running, the body weight of model (OVO) group, exercise (OVE) group and NC group had significant statistical significance (P<0.01). It was found that the weight of OVE group was much more as compared to OVO group. There was significant difference in body weight between OVO group and NC group (P<0.05). After LIPUS treatment, it was found that the weight of OVO group, OVE group, LIPUS group and OVE +LIPUS group increased. Compared with the NC group, there was significant statistical difference (P<0.01). Conclusion: Low intensity pulsed ultrasound ITI has a good effect on improving MA, so as to effectively improve the weight of gastrocnemius muscle. The combined application of the two is better for the improvement of muscular atrophy. [ABSTRACT FROM AUTHOR]

Objective: Exercise has been reported to be beneficial for people with type 2 diabetes (T2DM), but exercise, especially weight-bearing exercise, may increase the risk of diabetic foot ulcers (DFUs). This study aimed to explore the associations between different volumes of weight-bearing physical activities and plantar microcirculation and tissue hardness in people with T2DM.Methods: 130 elderly people with T2DM were enrolled for this cross-sectional study. They were classified into the high exercise volume group and the low exercise volume group based on their weekly energy expenditure (metabolic equivalents per week) in the past year. Weekly energy expenditure was calculated using the International Physical Activity Questionnaire and the Compendium of Physical Activities. The plantar oxygen saturation (SO2) and soft tissue hardness of each participant’s right foot were measured.Results: A total of 80 participants completed the trial. The average exercise energy expenditure of the high exercise volume group and the low exercise volume group were significantly different (p < 0.05). The results showed that the SO2 of the high exercise volume group (67.25 ± 6.12%) was significantly higher than the low exercise volume group (63.75 ± 8.02%, p < 0.05). The plantar tissue hardness of the high exercise volume group was lower than the low exercise volume group in the big toe, midfoot and hindfoot regions (p < 0.05).Conclusion: This study demonstrates that higher volumes of exercise are associated with better plantar microcirculation and lower plantar tissue hardness in people with T2DM. The findings of this study indicate that weight-bearing exercise may not increase risk of developing diabetic foot ulcers.

Background: Exercise, especially weight-bearing exercise (e.g. walking), may affect plantar tissue viability due to prolonged repetitive high vertical and high shear pressure stimulus on the plantar tissue, and further induce development of diabetic foot ulcers (DFUs). This study aimed to investigate the effects of different accumulated pressure-time integral (APTI) stimuli induced by walking on plantar skin blood flow (SBF) responses in people with diabetes mellitus (DM).Methods: A repeated measures design was used in this study. Two walking protocols (low APTI (73,000 kPa·s) and high APTI (73,000 × 1.5 kPa·s)) were randomly assigned to ten people with DM and twenty people without DM. The ratio of SBF measured by laser Doppler flowmetry after walking to that before (normalized SBF) was used to express the SBF responses.Results: After low APTI, plantar SBF of people with DM showed a similar response to people without DM (P = 0.91). However, after high APTI, people with DM had a significantly lower plantar SBF compared to people without DM (P < 0.05). In people with DM, plantar SBF in the first 2 min after both APTI stimuli significantly decreased compared to plantar SBF before walking (P < 0.05).Conclusions: People with DM had a normal SBF response after low APTI walking but had an impaired SBF response after high APTI walking, which suggests that they should avoid weight-bearing physical activity with intensity more than 73,000 kPa·s and should rest for more than 2 min after weight-bearing physical activity to allow a full vasodilatory response to reduce risk of DFUs. [ABSTRACT FROM AUTHOR]

Skeletal muscle atrophy (SMA) is a dominant symptom induced by estrogen deficiency which can lead to severe health problems of postmenopausal women. Furthermore, estrogen deficiency has severely compromised the maintenance of muscle stem cells as well as impairs self-renewal and differentiation into muscle fibers. Resistance training is commonly considered as a positive and useful intervention in accelerating the rate of muscle growth. As one of the resistance training, whether the weight-bearing exercise can alleviate SMA induced by estrogen deficiency has not been investigated. The rats were divided into 3 groups randomly: sham group, ovariectomized (OVX) group, and weight-bearing exercise (WBE) therapeutic group. The weight that rats were loaded was 35% of their body weight, and the rats were trained by treadmill training (5° slope, 20 m/min, 30 min/day, 6 days/week) for 8 weeks. After training, the quality and strength of skeletal muscle of the WBE rats were improved; meanwhile, the cross-sectional areas of the skeletal muscle were also increased. Moreover, the WBE activated Akt significantly, upregulated the expression of mTOR, and downregulated the expression of MSTN and its receptor ActRIIB and FoxO1, respectively. The SMA phenomena of rats which induced by estrogen deficiency were prevented effectively via WBE, and the MSTN/Akt/mTOR and FoxO1 signaling pathway may be the predominant way in this improvement. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the logical and ecological validity of 5 explosive push-up variations as a means of upper-body power assessment, using the factorial characterization of ground reaction force-based (GRF-based) parameter outputs. Thirty-seven highly active commando soldiers (age: 23.3 ± 1.5 years; body mass: 78.7 ± 9.7 kg; body height: 179.7 ± 4.3 cm) performed 3 trials of 5 variations of the explosive push-up in a randomized-counterbalanced order: (a) standard countermovement push-up, (b) standard squat push-up, (c) kneeling countermovement push-up, (d) kneeling squat push-up, and (e) drop-fall push-up. Vertical GRFwas measured during these exercises using a portable force plate. The initial force-supported, peak-GRF and rate of force development during takeoff, flight time, impact force, and rate of force development impact on landing were measured. A significant relationship between initial force-supported and peak-GRF takeoff was observed for the countermovement push-up (CMP) exercises (standard countermovement push-up, kneeling countermovement push-up, and drop-fall push-up) and squat push-up (SP) exercises (standard squat push-up and kneeling squat push-up) (r = 0.58 and r = 0.80, respectively; p < 0.01). Furthermore, initial force supported was also negatively correlated to a significant degree with flight time for both CMP and SP (r = -0.74 and r = -0.80; p < 0.01, respectively). Principal component analysis (PCA) showed that the abovementioned 6 GRF-based variables resulted in the extraction of 3 significant components, which explained 88.9% of the total variance for CMP, and 2 significant components, which explained 71.0% of the total variance for SP exercises. In summary, the PCA model demonstrated a great predictive power in accounting for GRF-based parameters of explosive push-up exercises, allowing for stronger logical and ecological validity as tests of upper-body power. Furthermore, it is possible to adjust the intensity level of the push-up exercise by altering the starting position (i.e., standard vs. kneeling). [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the acute response of biochemical bone turnover markers (BTM) to high-impact jumping exercise, and to quantify the ground reaction forces (GRF) achieved during each jumping exercise, in postmenopausal women. In a randomized controlled cross-over study over three days, 29 postmenopausal women (age (mean±SD): 60.0±5.6 years) were randomly assigned to 6 x 10 repetitions of three different jumps: countermovement jump (CMJ), drop jump (DJ), diagonal drop jump (DDJ). A fourth day without jumping served as a control (CON). Blood samples were collected before (PRE), after (POST), and 2 hours after (2Hr) exercise. Bone turnover was evaluated by bone formation markers (procollagen type-1 aminoterminal propeptide (P1NP) and osteocalcin (OC)) and the bone resorption marker C-terminal telopeptide of type-1 collagen (CTX). Peak anteroposterior (Fx), mediolateral (Fy), and vertical (Fz) GRF were measured using a force platform. From PRE to POST, P1NP increased (p<0.01) by 7.7±1.8%, 9.4±1.3%, and 10.6±1.6% for CMJ, DJ, and DDJ, which were higher (p<0.01) than CON. OC increased (p<0.05) by 5.5±1.8% for DJ, which was higher (p<0.05) than CON. CTX was not significantly changed at POST. There were no significant differences in BTM Δ-values between the jumps at any time point. For the CMJ, the combined three-axis peak GRF was positively associated with the PRE to POST Δ-change in P1NP (r=0.71, p<0.05). The acute, jumping-induced increase in P1NP and OC without any rise in CTX may indicate increased bone formation. Moreover, the study shows a dose-response relationship between GRF and the acute P1NP response after countermovement jumps [ABSTRACT FROM AUTHOR]

Objectives The purpose of this research was to study the effect of eight weeks of weight-bearing exercise and acute caffeine supplementation on reaction time in elderly women. Methods & Materials The research method was quasi-experimental with pretest-posttest design. The study subjects comprised 43 menopausal, inactive women with mean [SD] age of 55.69 [5.88] years who were randomly assigned into three groups of training (15 persons), caffeine (15 persons), and control (13 persons). The training protocol was performed over 8 weeks. The control group was not part of the exercise program. The body composition analyzer and simple and choice reaction time instrument were applied. Dependent t test and 1-way ANOVA test with post hoc Tukey test were applied to analyze the data. Results The results suggested that weight-bearing exercises had a significant effect on simple reaction time (sound) while it was not significantly different in simple reaction time (voice) (P=0.003, P= 0.003, and P= 0.09, respectively). It was also found that caffeine intake (2 mg/kg) had no significant effect on reaction time (P=0.12). Conclusion Weight-bearing training can be effective in improving the reaction time of the elderly.

Purpose: Weight-bearing activities such as running have been shown to be osteogenic. However, investigations have also shown that running may lead to site-specific deficiencies in bone mineral density (BMD) as well as overall low BMD. The purpose of this investigation was to evaluate and compare the BMD of female and male collegiate cross-country runners with non-running controls. In addition, energy availability and disordered eating attitudes and behaviors were assessed.Methods: BMD of 60 collegiate cross-country runners and 47 BMI and age-matched non-running controls were measured via DXA scans. Participants completed a Block 2014 Food Frequency Questionnaire and Eating Disorder Examination Questionnaire.Results: Controlling for fat-free mass (FFM), male runners showed greater BMD at the femoral neck (0.934 ± 0.029 vs. 0.866 ± 0.028 g cm2, p < 0.05), total hip (1.119 ± 0.023 vs. 1.038 ± 0.021 g cm2, p < 0.05), and whole body (1.119 ± 0.023 vs. 1.038 ± 0.021 g cm2, p < 0.05) than male controls. The female runners had greater whole-body BMD than female controls (1.143 ± 0.018 vs. 1.087 ± 0.022 g cm2, p < 0.05). Runners scored significantly higher than controls in dietary restraint (1.134 ± 1.24 vs. 0.451 ± 0.75, p < 0.05), male runners were significantly higher than male controls in eating concern (1.344 ± 1.08 vs. 0.113 ± 0.27, p < 0.05) and female runners were significantly higher than male runners in shape concern (1.056 ± 1.27 vs. 0.242 ± 0.31, p < 0.05). Forty-two percent of the male runners and 29% of female runners had an energy availability of less than 30 kcals kg-1FFM.Conclusion: It appears that distance running has beneficial effects on whole-body BMD and site-specific areas. Further research is warranted to further clarify the health effects of eating behaviors and EA of distance runners. [ABSTRACT FROM AUTHOR]

Purpose: The purpose was to explore the feasibility of whole body vibration (WBV) on polio survivors with/without post-polio syndrome (PPS) by studying its effects on walking speed (10-m walk test), endurance (2-min walk test), pain severity/interference (Brief Pain Inventory [BPI]), sleep quality (Pittsburg Sleep Quality Index), fatigue (Fatigue Severity Scale), leg strength (manual muscle testing and hand-held dynamometry), and muscle cramping (written logs). Methods: Fifteen individuals completed the study, participating in eight sessions in two 4-week blocks. Participants started with ten 1-min vibration bouts/session, increasing to 20 min. Low (amplitude 4.53 mm, g force 2.21) and higher (amplitude 8.82 mm, g force 2.76) intensity blocked intervention occurred in random order crossover design. Blinded testing ensued before/after intervention blocks and at follow-up. Results: No study-related adverse events occurred. Participants starting first with higher intensity intervention improved in walking speed (p = 0.017). BPI pain severity significantly improved (p = 0.049) after higher intensity intervention. No significant changes were found after low intensity vibration or in other outcome measures. Conclusions: WBV appears to be a safe exercise for this population. Long-term use in polio survivors needs to be researched, particularly in reducing barriers to participation to promote the physical aspects of health. [ABSTRACT FROM AUTHOR]

Background & Objective: One of the most serious health problems is osteoporosis and it is mandatory to find preventive methods to confront this difficulty. Non-pharmacological methods are in priority due to less side effects. This study investigated the effect of treadmill running exercise on bone microarchitectures in female osteoporotic rats induced by ovariectomy. Materials & Methods: 30 rats were randomly divided into three groups of control, experimental one, and experimental two. Control and Experimental one (Ovariectomized) groups were kept in control conditions. The Experimental group two was subjected to 10 weeks treadmill running exercise from the 12th- post operative week. The animals were weighted in all the stages of the protocol. Finally, all rats were sacrificed and their femoral bones were removed for bone strength and bone microarchitectures analysis by using One-Way ANOVA test. The Repeated Measure was used to analyze the weight changes during the study. Results: The results showed that despite the same initial weight among groups (P=0.31), weight increased significantly in 12th and 22th postoperative weeks (P

(Received 4 April, 2009; Accepted 17 June, 2009)AbstractBackground and purpose: Osteoporotic fractures are much more common in older post-menopausal women and account for significant morbidity and mortality. Although age is an independent risk factor for fractures, bone micro-architecture is the predictor of subsequent fractures. Adequate calcium and Weight-bearing exercise are known to affect skeletal development, however, the effects of calcium supplement and treadmill endurance running on bone micro-architecture are not well known. The objective of this study was to determine the effects of treadmill endurance running training and calcium supplement, on micro-architectures of cortical and trabecular bone in the proximal tibia metaphyseal in ovariectomized Sprague Dawley rats.Materials and methods: Forty-three rats were randomly divided into endurance running training, calcium supplement, control, pre-test and base groups. The rats in the treadmill running group performed the progressive running exercise in 12 to 20 m/minutes for a total of 10 to 60 minutes, 5 times a week. Calcium group received ca supplement using Gavage (35 mg/kg/day) for 8 weeks. After 8 weeks, micro-architecture parameters in the proximal tibia metaphyseal were measured by using a semi-automated image analysis system.Results: The ovariectomay was associated with a significant decrease in the trabecular volume and thickness, while separation insignificantly decreased in the cortical volume and thickness in the proximal tibia metaphyseal. The treadmill running exercise and calcium supplement significantly increased cortical or trabecular volume and also thickness and the trabecular separation compared with age-matched controls. Furthermore, the micro-architectures of cortical and trabecular bone in the proximal tibia metaphyseal was insignificant between the treadmill endurance running and calcium supplement groups.Conclusion: Skeletal benefits can be obtained by changes in life style including: weight-bearing exercise or calcium supplement. Furthermore, weight-bearing exercise or calcium supplement, followed by ovariectomay had an inhibitory effect or reversal on micro-architecture parameters in weight-bearing bones.Key words: J Mazand Univ Med Sci 2009; 19(70): 18-25 (Persian)

Background and objective Obesity is associated with increased dyspnoea and reduced health status in patients with chronic obstructive pulmonary disease ( COPD). Studies on the effects of obesity on exercise capacity showed divergent results. The objective of this study is to investigate the impact of obesity on weight-bearing versus weight-supported exercise tolerance in obese and normal weight patients, matched for age, gender and degree of airflow limitation. Methods Retrospective analyses of data obtained during pre-pulmonary rehabilitation assessment in 108 obese COPD patients ( OB) (age: 61.2 ± 5.3y, FEV1: 43.2 ± 7.4%, BMI: 34.1 ± 3.9 kg/m2,) and 108 age and FEV1-matched normal weight COPD patients ( NW) (age: 61.7 ± 3.6y, FEV1: 41.5 ± 8.4%, BMI: 22.9 ± 1.2 kg/m2,). Cardiopulmonary exercise test ( CPET) and 6 min walk test (6 MWT) were performed, Borg scores for dyspnoea and leg fatigue were recorded, before and after the tests. Results Six-minute walk distance differed between OB (398 ± 107 m) and NW patients (446 ± 109 m, P < 0.05), while peak cycling exercise load was comparable ( OB: 75 ± 29 W, NW: 70 ± 25 W, ns). Dyspnoea ( OB 3.2 ± 2.0 vs NW 3.1 ± 1.7, ns) and leg fatigue ( OB 2.4 ± 2.3 vs NW 1.9 ± 1.7, ns) were not significantly different in OB compared with NW after 6MWT, or after CPET (dyspnoea: OB 5.1 ± 2.4 vs NW 5.4 ± 2.2, ns; leg fatigue: OB 4.0 ± 2.3 vs NW 4.0 ± 2.7, ns). Conclusion In contrast to weight-supported exercise, obesity has a negative impact on weight-bearing exercise capacity, despite comparable exercise-related symptoms. The results of this study enhance the understanding of the impact of obesity on physical performance in COPD. [ABSTRACT FROM AUTHOR]

Background: Physical activity (PA), weight-bearing exercises (WBE) and muscle strength contribute to skeletal development, while sedentary behaviour (SB) adversely affects bone health. Previous studies examined the isolated effect of PA, SB or muscle strength on bone health, which was usually assessed by x-ray methods, in children. Little is known about the combined effects of these factors on bone stiffness (SI) assessed by quantitative ultrasound. We investigated the joint association of PA, SB and muscle strength on SI in children. Methods: In 1512 preschool (2- < 6 years) and 2953 school children (6-10 years), data on calcaneal SI as well as on accelerometer-based sedentary time (SED), light (LPA), moderate (MPA) and vigorous PA (VPA) were available. Parents reported sports (WBE versus no WBE), leisure time PA and screen time of their children. Jumping distance and handgrip strength served as indicators for muscle strength. The association of PA, SB and muscle strength with SI was estimated by multivariate linear regression, stratified by age group. Models were adjusted for age, sex, country, fat-free mass, daylight duration, consumption of dairy products and PA, or respectively SB. Results: Mean SI was similar in preschool (79.5 ± 15.0) and school children (81.3 ± 12.1). In both age groups, an additional 10 min/day in MPA or VPA increased the SI on average by 1 or 2 %, respectively (p ≤ .05). The negative association of SED with SI decreased after controlling for MVPA. LPA was not associated with SI. Furthermore, participation in WBE led to a 3 and 2 % higher SI in preschool (p = 0.003) and school children (p < .001), respectively. Although muscle strength significantly contributed to SI, it did not affect the associations of PA with SI. In contrast to objectively assessed PA, reported leisure time PA and screen time showed no remarkable association with SI. Conclusion: This study suggests that already an additional 10 min/day of MPA or VPA or the participation in WBE may result in a relevant increase in SI in children, taking muscle strength and SB into account. Our results support the importance of assessing accelerometer-based PA in large-scale studies. This may be important when deriving dose-response relationships between PA and bone health in children. [ABSTRACT FROM AUTHOR]

We aimed to determine the effect of past sporting activity on bone mineral content (BMC), areal bone mineral density (aBMD) in the lumbar spine and proximal femur, and bone geometry of the mid femur in young men and women. We assessed 142 subjects, comprising 79 young men (21.2 ± 0.8 years) and 63 premenopausal young women (21.4 ± 0.6 years). The subjects were classified into three groups, two on the basis of the age of starting to participate in sport [elementary school starters (6-12 years), junior high school to university starters (13-22 years)], and the third group had no participation in sport. We measured BMC and aBMD by dual-energy X-ray absorptiometry (DXA) in the lumbar spine and proximal femur, and bone geometric characteristics of the mid femur by magnetic resonance imaging (MRI), and calculated the osteogenic index (OI) of previous sporting activity. The OI correlated significantly with many MRI-determined measures of bone geometry; DXA-measured BMC and aBMD were effective indicators of previous sporting activity in both sexes. The female elementary school starters had significantly greater femoral mid-diaphyseal perimeters (vs the no-sport group), bone cross-sectional area (vs the 13-22-year-old starters and the no-sport group), and maximum and minimum second moment of area at the mid-diaphysis point of the femur (vs the no-sport group). The OI is a proven practicable and useful index. DXA- and MRI-determined geometric characteristics showed that high-impact, weight-bearing exercise before and in early puberty induces greater total proximal femur BMC and enhances femoral mid-diaphyseal size and shape, and that these benefits persisted in young adult women. [ABSTRACT FROM AUTHOR]

Background & Objective: One of the most serious health problems is osteoporosis and it is mandatory to find preventive methods to confront this difficulty. Non-pharmacological methods are in priority due to less side effects. This study investigated the effect of treadmill running exercise on bone microarchitectures in female osteoporotic rats induced by ovariectomy. Materials & Methods: 30 rats were randomly divided into three groups of control, experimental one, and experimental two. Control and Experimental one (Ovariectomized) groups were kept in control conditions. The Experimental group two was subjected to 10 weeks treadmill running exercise from the 12th- post operative week. The animals were weighted in all the stages of the protocol. Finally, all rats were sacrificed and their femoral bones were removed for bone strength and bone microarchitectures analysis by using One-Way ANOVA test. The Repeated Measure was used to analyze the weight changes during the study. Results: The results showed that despite the same initial weight among groups (P=0.31), weight increased significantly in 12th and 22th postoperative weeks (P<0.001). Ovariectomy induced a significant decrease in Trabecular Thickness (TT) and Cortical Thickness (CT) (P<0.001). It also induced a weakened femoral bone strength (P=0.003). The levels of TT, CT, and bone strength increased in experimental group two compared to experimental group one and Trabecular Separation (TS) decreased, either (P<0.001). Conclusion: The results indicated that a moderate intensity treadmill running exercise has a protective effect on osteoporotic bones. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a skeletal disease associated with high morbidity, mortality and increased economic costs. Early prevention during adolescence appears to be one of the most beneficial practices. Exercise is an effective approach for developing bone mass during puberty, but some sports may have a positive or negative impact on bone mass accrual. Plyometric jump training has been suggested as a type of exercise that can augment bone, but its effects on adolescent bone mass have not been rigorously assessed. The aims of the PRO-BONE study are to: 1) longitudinally assess bone health and its metabolism in adolescents engaged in osteogenic (football), non-osteogenic (cycling and swimming) sports and in a control group, and 2) examine the effect of a 9 month plyometric jump training programme on bone related outcomes in the sport groups. Methods/Design: This study will recruit 105 males aged 12-14 years who have participated in sport specific training for at least 3 hours per week during the last 3 years in the following sports groups: football (n = 30), cycling (n = 30) and swimming (n = 30). An age-matched control group (n = 15) that does not engage in these sports more than 3 hours per week will also be recruited. Participants will be measured on 5 occasions: 1) at baseline; 2) after 12 months of sport specific training where each sport group will be randomly allocated into two sub-groups: intervention group (sport + plyometric jump training) and sport group (sport only); 3) exactly after the 9 months of intervention; 4) 6 months following the intervention; 5) 12 months following the intervention. Body composition (dual energy X-ray absorptiometry, air displacement plethysmography and bioelectrical impedance), bone stiffness index (ultrasounds), physical activity (accelerometers), diet (24 h recall questionnaire), pubertal maturation (Tanner stage), physical fitness (cardiorespiratory and muscular), bone turnover markers and vitamin D will be measured at each visit. Discussion: The PRO-BONE study is designed to investigate the impact of osteogenic and non-osteogenic sports on bone development in adolescent males during puberty, and how a plyometric jump training programme is associated with body composition parameters. [ABSTRACT FROM AUTHOR]

Context: Osteoporosis is a major public health concern worldwide. Understanding the roles of diet and physical activity in ensuring adequate bone mass accrual during childhood and adolescence may help identify strategies to reduce the risk of osteoporotic fractures later in life. Objective: The present systematic review was conducted to provide an overview of the current knowledge of the combined effects of physical activity and diet on bone mass accrual in children and adolescents. Data Sources: Data were obtained via searches of the PubMed, EMBASE, SPORTDiscus, and ISI Web of Science databases. Study Selection: Studies published in English and Spanish between 1887 and August 2013 were eligible for inclusion. Two investigators evaluated the studies against the inclusion and exclusion criteria. A total of 14 studies (7 cross-sectional and 7 experimental) were included in the review. Data Extraction: The Pedro score and the Black and Down's checklist were used to evaluate the methodological quality of the experimental and the cross-sectional studies, respectively. Study characteristics were summarized in accordance with the review's PICO criteria. Data Synthesis: Significant exercise-by-calcium interaction was detected at several different bone sites. Conclusions: Although the results of cross-sectional studies were inconsistent, the results of randomized controlled trials showed that exercise has the potential to improve bone health under conditions of adequate calcium intake. [ABSTRACT FROM AUTHOR]

Background: This investigation compared the effects of an extended period of weight-bearing (running) vs. non-weight-bearing (cycling) exercise on hepcidin production and its implications for iron status. Methods: Ten active males performed two separate exercise training blocks with either running (RTB) or cycling (CTB) as the exercise mode. Each block consisted of five training sessions (Day 1, 2, 4, 5, 6) performed over a seven day period that were matched for exercise intensity. Basal venous blood samples were obtained on Day 1 (D1), and on Recovery Days 3 (R3) and 7 (R7) to assess iron status, while basal and 3 h post-exercise urinary hepcidin levels were measured on D1, D2, D6, as well as R3 and R7 (basal levels only) for each condition. Results: Basal urinary hepcidin levels were significantly elevated (p ≤ 0.05) at D2, R3 and R7 as compared to D1 in RTB. Furthermore, 3 h post-exercise urinary hepcidin levels on D1 were also significantly higher in RTB compared to CTB (p ≤ 0.05). In CTB, urinary hepcidin levels were not statistically different on D1 as compared to R7. Iron parameters were not significantly different at D1 compared to R3 and R7 during both conditions. Conclusions: These results suggest that basal hepcidin levels may increase over the course of an extended training program, especially if a weight-bearing exercise modality is undertaken. However, despite any variations in hepcidin production, serum iron parameters in both RTB and CTB were unaffected, possibly due to the short duration of each training block. In comparing running to cycling, non-weight-bearing activity may require more training sessions, or sessions of extended duration, before any significant changes in basal hepcidin levels appear. Chronic elevations in hepcidin levels may help to explain the high incidence of iron deficiency in athletes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Weight bearing exercise improved bone mineral density on children with Down syndrome. [•] Enriched cow milk with vitamin D (calcium supplementation) had positive effect on bone mineral density. [•] Weight bearing exercise with calcium supplementation resulted in a greater increase in BMD than training or calcium alone. [Copyright &y& Elsevier]

Abstract: This study examines the effects of 32 weeks of exercise training on balance, lower-extremity muscle strength, bone mineral density (BMD) and serum levels of bone metabolism and inflammatory markers in older adults. Forty-seven healthy older adults (women=24, men=23; mean age 68.2 years) participated in a exercise intervention (60min/session) that included resistance exercise training (2 days/week) at 75–80% of maximum plus a multicomponent weight-bearing impact exercise training (1 day/week). Outcome measures included lumbar spine and proximal femoral BMD, dynamic balance, muscle strength, serum levels of bone metabolism markers [osteocalcin (OC), C-terminal telopeptide of Type I collagen (CTX), osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL)] and serum levels of inflammatory markers [high sensitive (hs)-C-reactive protein (CRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ]. Potential confounding variables included body composition, dietary intake (using 4-day diet records), and accelerometer-based physical activity. After 32 weeks, both men and women increased dynamic balance (6.4%), muscle strength (11.0%) and trochanter (0.7%), intertrochanter (0.7%), total hip (0.6%), and lumbar spine BMD (1.7%), while OC, CTX, OPG and RANKL levels remained unchanged. In addition, hs-CRP and IFN-γ levels were decreased, while TNF-α levels were unchanged, and a decrease in IL-6 levels was only observed in men. These findings suggest that our combined impact protocol reduces inflammation and increases BMD, balance, and lower-extremity muscle strength, despite having little effect on bone metabolism markers. This reinforces the role of exercise to counteract the age-related inflammation, and the muscle strength, balance and BMD reduction. [Copyright &y& Elsevier]

This study was designed to evaluate whether a weight-bearing exercise training played 3 times a week can have benefits on bone mineral density and neuromuscular function in women with a diagnosis of osteopenia. The study enrolled 22 women aged between 45 and 65, with densitometric diagnosis of osteopenia. The participants were randomly assigned to a group of exercise (n=ll) and a control group (n=ll). The exercise program lasted for 45 min and consisted of a combination of strength exercises that seek to cause a mechanical osteoblastic stimulus by use of gravity, body weight, fall with anti-gravity reaction, in combination with exercises for the improvement of balance and coordination. The outcome measures used to assess the result on bone mass are the bone Mineralometric DEXA method for femoral head-neck region and lumbar spine and biochemical markers of bone turnover (resorption and neoformation) and for the evaluation of neuromuscular function was chosen to use surface electromyography (sEMG) as an indicator of overall activity and speed activation of lumbar paravertebral muscles and of the lower limbs antigravity muscles, stabilometric analysis and 6' Walk Test. In addition each person enrolled was given EuroQol and ICF core set of osteoporosis, respectively, to assess the quality of life, as well as activity limitations and participation restrictions associated. In the exercise group, mean values and changes in average rates for the balance, muscle strength, walking ability and quality of life, mean bone mineral content and bone turnover markers, corresponding to the assessments made at 0 (before rehabilitation intervention) and Time 1 (program ended), showed a statistically significant improvement. The results of this study demonstrate that a group rehabilitation program of exercises based on gravitational load, aimed to improve muscle strength and trophism, coordination and balance, can provide advantages of unquestionable importance, not only on the slope of increase bone mass of neuromuscular function and reducing risk of falling, but on health in general. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to investigate the effects of weight bearing exercise and calcium intake on bone mineral density (BMD) of students with autism spectrum disorders. For this reason 60 boy students with autism disorder (age 8–10 years old) were assigned to four groups with no differences in age, BMD, calcium intake, and physical activity: exercise groups with or without calcium supplementation (Ex+Ca+ and Ex+Ca−) and non-exercise groups with or without calcium supplementation (Ex−Ca+ and Ex−Ca−). The intervention involved 50min of weight bearing exercise performed 3 sessions a week and/or the addition of dietary calcium rich food using enriched cow milk with vitamin D containing 250mg calcium per serving, over 6 months. Paired-samples t test, one way ANOVA analysis, and Tukey tests were used to determine the main and combined effects of training and calcium on BMD. All groups showed greater femoral neck BMD after 6 months. The increase in femoral neck BMD in the Ex+Ca+ group was 14.04% greater than increase in the Ex+Ca− group (P <0.05). Apparently, the effect of training was greater than calcium intake because the Ex+Ca− group achieved 4.71% greater BMD than Ex−Ca+ group (P <0.05). In this study, all experimental groups had greater BMD than the control group (Ex−Ca−) (P <0.05). In these participants, additional weight bearing exercise and calcium supplementation resulted in a greater increase in BMD than controls at the loaded site (femoral neck). These results help to provide more evidence for public health organizations to deal with both exercise and nutrition issues in children with autism disorder for the achievement and of peak BMD. [Copyright &y& Elsevier]

Physical exercise is advised as a preventive and therapeutic strategy against aging-induced bone weakness. In this study we examined the effects of 8-month multicomponent training with weight-bearing exercises on different risk factors of falling, including muscle strength, balance, agility, and bone mineral density (BMD) in older women. Participants were randomly assigned to either an exercise-training group (ET, n = 30) or a control group (CON, n = 30). Twenty-seven subjects in the ET group and 22 in the CON group completed the study. Training was performed twice a week and was designed to load bones with intermittent and multidirectional compressive forces and to improve physical function. Outcome measures included lumbar spine and proximal femoral BMD (by dual X-ray absorptiometry), muscle strength, balance, handgrip strength, walking performance, fat mass, and anthropometric data. Potential confounding variables included dietary intake, accelerometer-based physical activity, and molecularly defined lactase nonpersistence. After 8 months, the ET group decreased percent fat mass and improved handgrip strength, postural sway, strength on knee flexion at 180°/s, and BMD at the femoral neck (+2.8%). Both groups decreased waist circumference and improved dynamic balance, chair stand performance, strength on knee extension for the right leg at 180°/s, and knee flexion for both legs at 60°/s. No associations were found between lactase nonpersistence and BMD changes. Data suggest that 8 months of moderate-impact weight-bearing and multicomponent exercises reduces the potential risk factors for falls and related fractures in older women. [ABSTRACT FROM AUTHOR]

Growing bones are most responsive to mechanical loading. We investigated bone mass acquisition patterns following a swimming or running exercise intervention of equal duration, in growing rats. We compared changes in bone mineral properties in female Sprague Dawley rats that were divided into three groups: sedentary controls (n = 10), runners (n = 8) and swimmers (n = 11). Runners and swimmers underwent a six week intervention, exercising five days per week, 30min per day. Running rats ran on an inclined treadmill at 0.33 m.s-1, while swimming rats swam in 25°C water. Dual energy X-ray absorptiometry scans measuring bone mineral content (BMC), bone mineral density (BMD) and bone area at the femur, lumbar spine and whole body were recorded for all rats before and after the six week intervention. Bone and serum calcium and plasma parathyroid hormone (PTH) concentrations were measured at the end of the 6 weeks. Swimming rats had greater BMC and bone area changes at the femur and lumbar spine (p < 0.05) than the running rats and a greater whole body BMC and bone area to that of control rats (p < 0.05). There were no differences in bone gain between running and sedentary control rats. There was no significant difference in serum or bone calcium or PTH concentrations between the groups of rats. A swimming intervention is able to produce greater beneficial effects on the rat skeleton than no exercise at all, suggesting that the strains associated with swimming may engender a unique mechanical load on the bone. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to investigate the effects of physical training and calcium intake on bone mineral density (BMD) of students with mental retardation. Forty mentally retarded boys (age 7–10 years old) were randomly assigned to four groups (no differences in age, BMD, calcium intake and physical activity): training groups with or without calcium supplementation (Tr+Ca+ and Tr+Ca−) and nontraining groups with or without calcium supplementation (Tr−Ca+ and Tr−Ca−). The intervention involved 45min of physical training performed 3 sessions a week and/or the addition of dietary calcium-rich food using enriched cow milk with vitamin D containing 230mg calcium per serving, over 6 months. Paired-samples t-test and ANOVA analysis was used to determine the main and combined effects of training and calcium on BMD. All groups showed greater femoral neck BMD after 6 months. The increase in femoral neck BMD in the Tr+Ca+ group was 10% greater than increase in the Tr+Ca− group (not significant). Apparently, the effect of training was greater than calcium intake because the Tr+Ca− group achieved 4% greater BMD than Tr−Ca+ group (not significant). In this study, both training groups had greater BMD than the control group (Tr−Ca−) (P <0.05). In these participants with inadequate calcium intakes, additional exercise and calcium supplementation resulted in a 6–20% greater increase in BMD than controls at the loaded site (femoral neck). These results help to provide more evidence for public health organizations to deal with both exercise and nutrition issues in children for the achievement of peak BMD. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to determine calcaneal broadband ultrasound attenuation (BUA) of marathon race participants and compare this information with previously obtained normative data. BUA was assessed using the McCue CUBA clinical device in 217 male and 184 female runners, aged 20–93yr, participating in the 2004 Flora London Marathon. The normative data included 267 men and 334 women, aged 20–80yr. A significantly higher mean BUA (p <0.001) was observed for all the men (91.2dB/MHz, standard deviation [SD] 18.2dB/MHz) in the study compared to the women (81.6dB/MHz, SD 17.0dB/MHz) and for the marathon runners compared to the nonrunners (p <0.001) among men (97.2dB/MHz, SD 17.6dB/MHz and 87.7dB/MHz, SD 17.6dB/MHz, respectively) and women (89.2dB/MHz, SD 14.2dB/MHz and 77.4dB/MHz, SD 17.0dB/MHz, respectively). A significant decline in BUA with age was observed in all males and females, with the males starting from a higher baseline and with the rate of decline significantly ameliorated by marathon training (from −0.35 to −0.25dB/MHz per year in men and −0.51 to −0.15dB/MHz per year in women). This study provides observational evidence in support of the potential benefits of weight-bearing exercise, such as marathon training and running, on BUA of the calcaneus, an index of bone mineral density. [Copyright &y& Elsevier]

Bone biology is a complex and vastly growing area of study. It brings together the traditional fields of anatomy, physiology, and biomechanics with the increasingly complex fields of developmental biology and molecular genetics. For clinicians who treat bone disorders such as osteoporosis, developing a working knowledge of this topic is essential. This article discusses bone from a structural, anatomical, and functional perspective. It reviews skeletogenesis as a developmental process and from a regulatory perspective and presents biomechanical principles and theories. Osteoporosis is reviewed, including recent literature related to the role of exercise in prevention and treatment of this disease. [ABSTRACT FROM AUTHOR]

It is known that weight-bearing exercises under Ilizarov circular fixators (ICF) could enhance bone fracture healing by mechano-regulation. However, interfragmentary movements at the fracture site induced by weight-bearing may inhibit angiogenesis and ultimately delay the healing process. To tackle this challenge, a computational model is presented in this study which considers the spatial and temporal changes in mechanical properties of fracture callus to predict optimal levels of weight-bearing during fracture healing under ICF. The study takes sheep fractures as example and shows that the developed model has the capability of predicting patient specific, time-dependent optimal levels of weight-bearing which enhances mechano-regulation mediated healing without hindering the angiogenesis process. The results demonstrate that allowable level of weight-bearing and timings depend on fracture gap size. For normal body weights (BW) and moderate fracture gap sizes (e.g. 3 mm), weight-bearing with 30% BW could start by week 4 post-operation and gradually increase to 100% BW by week 11. In contrast, for relatively large fracture gap sizes (i.e. 6 mm), weight-bearing is recommended to commence in later stages of healing (e.g. week 11 post-operation). Furthermore, increasing ICF stiffness (e.g. using half pins instead of pretension wires) can increase the level of weight-bearing significantly in the early stages up to a certain time point (e.g. week 8 post-operation) beyond which no noticeable benefits could be achieved. The findings of this study have potential applications in designing post-operative weight bearing exercises. [Display omitted] • An approach to find optimal weight-bearing levels for fracture healing is presented. • Fracture site revascularization and bone resorption processes govern these levels. • Partial weight-bearing is recommended for Ilizarov fixators for longer periods. • Fixator configuration affects weight-bearing only in the early stages of healing. • Use of half pins is preferable over pretensioned wires in Ilizarov fixators. [ABSTRACT FROM AUTHOR]