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Background: Evidence suggests that the aging process tends to lead to sarcopenia and osteoporosis which reduce the quality of life in older women. Resistance training (RT) is widely supported as a means of delaying or offsetting the decline in muscle strength and loss of bone mineral content in older women. The purpose of this investigation was to analyze the effects of a 12-wk RT program (3 times a week) with dietary intake maintenance on muscle strength and body composition of healthy, sedentary older women., Methods: Forty-four older women were randomly assigned to a RT program (N.=22, 66.3±4.8 years, 60.7±9.1 kg, 153.1±0.90 cm, 24.9±3.3 kg/m²) or a control group (N.=22, 66.4±4.0 years, 63.3±7.5 kg, 155.5±5.8 cm, 26.2±2.6 kg/m²) performing stretching exercises during the same period. One-repetition maximum test on chest press and leg extension were used to assess muscle strength. Body composition was measured by dual energy x-ray absorptiometry to determine fat mass, fat-free mass, and bone mineral content. Dietary intake was recorded using a 3-day food records. All subjects maintained their normal diet during the investigation., Results: No significant differences were found for the body composition components within and between groups. A significant time by group interaction indicated that the RT group made greater improvements in upper and lower limb muscle strength (chest press ~12%, P=0.0001; leg extension ~13%, P<0.0001)., Conclusions: These results suggest that RT program improves muscle strength of major muscle groups, without altering body composition in older women under dietary intake maintenance.

Purpose: The purpose of this study was to examine the effects of acute L-arginine (L-arg) supplementation on peripheral vasodilatation and muscle performance in older women., Methods: In a double-blind, randomized, placebo-controlled study, 20 elderly women were randomly assigned in a double-blind fashion to either an L-arg (ARG, N = 10) or placebo (PLA, N = 10) group. During the first visit, both groups underwent a Doppler ultrasound exam (to assess the femoral artery vasodilatation) at rest (baseline), and immediately before and after the isokinetic strength test (performed at 80 min after supplementation). On the second and third visits, the groups completed a battery of muscle performance tests (to assess the isometric and functional strength), initiated at the same time point (80 min after supplementation)., Results: The femoral artery blood flow (ARG: 443.9 ± 42.8 vs. PLA: 373.1 ± 40.8 ml/min; P > 0.05) and area (ARG: 0.45 ± 0.03 vs. PLA: 0.41 ± 0.02 cm(2); P > 0.05) were similar between the groups at basal conditions, and they remained unchanged after supplementation. Following exercise, blood flow increased ~160 % above the basal level, and there was no significant (P > 0.05) difference between the ARG and PLA groups. Additionally, there were no significant (P > 0.05) differences between the ARG and PLA groups for any strength variable (isokinetic, isometric, and functional)., Conclusion: These results show that acute L-arg supplementation provides no ergogenic effect on blood flow and muscle performance in older women.

Background: The purpose of this study was to examine the effects of an additional set of exhaustive exercise before local muscular endurance (LME) training on maximal dynamic strength and endurance of quadriceps muscle in young men., Methods: Twenty-seven healthy men (age: 20.9±1.8 years) performed one repetition maximum (1RM), muscular endurance, and magnetic resonance imaging (MRI) tests on two separate occasions (before and after an 8-wk LME training program using a bilateral knee extensor machine). After baseline testing, the subjects were divided into three groups: untrained control (CO, N.=9), traditional training (TR, N.=9), and prior exhaustive training (PE, N.=9). Both the TR and PE groups trained using the same LME training protocol (2 d∙wk-1; 3 sets of 15-20 repetitions at 50% of 1RM) throughout the 8-wk experimental period; the only difference was that the PE group performed an additional set of exhaustive exercise at 80% of 1RM immediately before each training session., Results: After 8 wk, the PE group experienced a greater (P<0.05) increase in 1RM, endurance, and work efficiency than the TR group. Additionally, no changes (P>0.05) in cross-sectional area (CSA), body mass and daily dietary intake were observed from pre- to post-test in either group., Conclusions: These results suggest that the inclusion of a single set of exhaustive exercise at 80% of 1RM immediately before LME training can be a suitable strategy for inducing additional beneficial effects on quadriceps strength and endurance in young men.

The purpose of this study was to investigate the effect of resistance training on resting blood pressure and heart rate variability in elderly postmenopausal women. 29 untrained, non-hypertensive elderly women were randomly assigned to 2 groups: an intervention group (n=15, 65.5±5.0 years, 57.3±6.5 kg, 156.7±5.1 cm) that underwent a supervised resistance training program (8 exercises, 2 sets, 10-15 repetitions, 3 times/week) or a control group (n=14, 66.2±4.1 years, 61.1±11.7 kg, 157.5±7.1 cm) that participated in a supervised stretching program (25-30 min/session, 2 times/week). Resting auscultatory blood pressure, heart rate variability, evaluated from short recordings in a seated position, and maximal dynamic strength (1-RM test) were measured at baseline and after 12 weeks. A group x time ANOVA revealed that muscular strength increased significantly in the resistance training group (+ 10.2% for bench press and +12.7% for leg extension, P<0.05). Systolic blood pressure was reduced significantly in the resistance training group from pre- to post-intervention period (- 5 mmHg; P<0.05), while no significant effect was noted for diastolic blood pressure and heart rate variability indexes (P>0.05). None of these variables changed in the control group throughout the study. In conclusion, a supervised resistance training program improved muscular strength and reduced systolic blood pressure without affecting diastolic blood pressure and heart rate variability in elderly postmenopausal women., (© Georg Thieme Verlag KG Stuttgart · New York.)

Strength is a fundamental component of physical fitness, and therefore should be precisely assessed. The purpose of this study was to analyze the number of testing sessions required to achieve consistent 1 repetition maximum (1RM) strength measurements in untrained older women. Forty-five untrained older women were measured for 1RM in bench press machine (BP), leg extension (LE) machine, and free weight arm curl (AC). Reliability coefficients for trials 1 and 2 for BP (intraclass correlation coefficient [ICC] = 0.973) and LE (ICC = 0.976) were higher than for AC (ICC = 0.953). Percent change from trial 1 to 2 for BP (3.5 ± 10.9%) and AC (3.8 ± 8.1%) was less than for LE (5.4 ± 6.2%), but all were significant increases between trials (p < 0.05). Trial differences were reduced to nonsignificant levels (p > 0.05) in the third trial for BP (0.0 ± 0.0%), LE (1.2 ± 3.0%) and AC (2.7 ± 5.9%). Reliability coefficients rose for BP and LE (ICC = 0.999) and AC (ICC = 0.963) when a third trial was performed. Bland and Altman plotting showed very small bias and limits of agreement (LoA) for both the exercises (BP: bias = 0 kg, limits of agreement = 0 kg; LE: bias = -0.16 kg, LoA = 2.21 kg; AC: bias = -0.11 kg, LoA = 1.72 kg). This approach to determine 1RM strength values produced rapid lifting technique familiarization resulting in a need of 2 to 3 test sessions to achieve consistent 1RM measurements in untrained older women.

This study examined the effects of long-term creatine supplementation combined with resistance training (RT) on the one-repetition maximum (1RM) strength, motor functional performance (e.g., 30-s chair stand, arm curl, and getting up from lying on the floor tests) and body composition (e.g., fat-free mass, muscle mass, and % body fat using DEXA scans) in older women. Eighteen healthy women (64.9 ± 5.0 years) were randomly assigned in a double-blind fashion to either a creatine (CR, N = 9) or placebo (PL, N = 9) group. Both groups underwent a 12-week RT program (3 days week(-1)), consuming an equivalent amount of either creatine (5.0 g day(-1)) or placebo (maltodextrin). After 12 week, the CR group experienced a greater (P < 0.05) increase (Δ%) in training volume (+164.2), and 1RM bench press (+5.1), knee extension (+3.9) and biceps curl (+8.8) performance than the PL group. Furthermore, CR group gained significantly more fat-free mass (+3.2) and muscle mass (+2.8) and were more efficient in performing submaximal-strength functional tests than the PL group. No changes (P > 0.05) in body mass or % body fat were observed from pre- to post-test in either group. These results indicate that long-term creatine supplementation combined with RT improves the ability to perform submaximal-strength functional tasks and promotes a greater increase in maximal strength, fat-free mass and muscle mass in older women.

Objective: To verify the association between nutritional status, physical fitness, and body image in children and adolescents., Methods: This cross-sectional study included 401 students (236 boys and 165 girls) aged between 8 and 16 years that were regularly enrolled in sports in the local clubs. The nutritional status was evaluated by the body mass index. Students were assessed for satisfaction with body image, abdominal strength resistance, and cardiorespiratory fitness. The variables were assessed on the same day following a standardized order. In order to verify relationships between variables, the chi-square test was used. Afterwards, the binary logistic regression was applied to identify the magnitude of the associations, considering p<0.05 as significant., Results: Association was found between body image and body mass index (p=0.001), abdominal strength resistance (p=0.005) and cardiorespiratory fitness (p=0.001). The Odds Ratio for presenting the body image insatisfaction for those who have not achieved the expected values for the health criteria in abdominal strength resistance and cardiorespiratory fitness were 2.14 and 2.42 times respectively, and for those with overweight and obesity, 2.87 times., Conclusions: Insatisfaction with body image is associated with body mass index and also with physical fitness, abdominal strength resistance, and cardiorespiratory fitness variables.

Background: It is unclear whether participation in exercise programs specifically developed for elderly translates into a more active lifestyle., Objectives: To compare the objectively measured level of physical activity in daily life (PADL) between physically independent elderly who participate or do not participate in community-based exercise programs; and to evaluate which factors are associated with the higher level of PADL in these subjects., Method: 134 elderly participants in community-based exercise programs (PG) and 104 non-participants (NPG) had their level of PADL measured using pedometers during 7 days., Other Measurements: 6-minute walking test (6MWT), incremental shuttle walking test (ISWT), muscle strength, flexibility and balance., Results: The PG had higher 1-week mean daily step count than NPG (8314 [IQR 5971-10060] vs. 6250 [IQR 4346-8207] steps/day, p<0.0001), as well as higher step count in any day of the week. There was a higher proportion of physically active subjects (>8000 steps/day) in PG than in NPG (37% vs. 16%, respectively; p<0.001), as well as the proportion of sedentary subjects (<5000 steps/day) (14% vs. 33%, respectively; p<0.001). Participation in exercise programs, 6MWT and ISWT explained a higher daily steps count (model r(2)=0.56, p<0.0001)., Conclusions: In physically independent elderly, a higher level of physical activity in daily life occurs in those who participate in community-based exercise programs, regardless of the weekday and including non-program days. Participation of elderly in community-based exercise programs should be more systematically available and encouraged due to its close link to higher activity levels and better exercise capacity.

The purpose of this cross-sectional study was to generate a functional-fitness profile for older women from the south of Brazil and to compare their functional profile with an age-matched cohort of American women. The Fullerton Functional Fitness Test (body-mass index, 6-min-walk test, chair sit-and-reach, chair stand, arm curl, and 8-ft up-and-go) was administered to 1,033 participants. Z scores indicate that older American women performed better in all functional tests than age-matched Brazilians. This fact could be explained by the delayed establishment of specific health policies for older adults in Brazil. In conclusion, the findings provide guidelines about the normal variation of functional fitness in older women from the southern region of Brazil. In addition, these data can be used to help identify older women with functional losses, thereby assisting in the diagnosis of early disability.