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PURPOSE Despite immense research highlighting maternal-fetal benefits of exercise during pregnancy, there remain concerns that exercise may undermine placental function. Although maternal exercise has demonstrated favorable aerobic conditioning responses in the mother, it is not known whether maternal exercise promotes increased angiogenesis in the placenta, perhaps at the expense of impaired endoplasmic reticulum (ER) homeostasis and/or oxidative stress. We investigated if a mild (30% heart rate reserve) and/or moderate (70% heart rate reserve) exercise regime in healthy pregnant women affected placental markers of angiogenesis, ER stress, and oxidative stress. We hypothesized that the improved aerobic conditioning of mothers who exercise is beneficial to enhance placental angiogenesis and normal maternal-fetal outcomes. METHODS Placental tissues were collected within 1 h of delivery from a convenience sample of 29 healthy mothers of full-term infants. Twenty-one women participated in routine exercise from midgestation (16-20 wk) until term of either mild or moderate intensity, whereas eight sedentary women served as controls. RESULTS No differences were identified between groups including gestational length, fetal-placental weight ratio, or APGAR scoring. All exercisers exhibited a significant 20-fold increase in the mRNA (as assessed by quantitative real-time polymerase chain reaction) and a 10-fold increase in the protein expression of angiogenin (e.g., ANG1) in the placenta. However, in both exercising groups, no increases in placental markers (i.e., HIF1α, VEGF), ER stress (i.e., spliced XBP1, ATF4, ATF6, CHOP, and BAX), or oxidative stress (i.e., SOD1, SOD2) were observed. CONCLUSIONS Overall, our study suggests that mild- and moderate-intensity exercise increases angiogenesis but does not increase placental oxidative or ER stress in healthy pregnancies, bolstering support for routine exercise as a part of standard care in pregnant women. Future studies are warranted to investigate the potential benefits of exercise on ANG1 in pathological pregnancies.

Chiarlitti, NA, Crozier, M, Insogna, JA, Reid, RER, and Delisle-Houde, P. Longitudinal physiological and fitness evaluations in elite ice hockey: A systematic review. J Strength Cond Res 35(10): 2963-2979, 2021-Ice hockey has greatly evolved since the last review article was published more than 25 years ago. Although players still combine anaerobic and aerobic conditioning, the pace of the game has greatly increased. Players are faster, stronger, and more agile than their predecessors; however, an important emphasis is now placed on maximizing player performance for the play-offs. For the coaching staff, strength and conditioning coaches, and players, an emphasis on mitigating fitness and physiologic losses throughout the season would be beneficial, given the intimate relationship they share with on-ice performance. This systematic review of the literature outlines the current knowledge concerning longitudinal changes in relation to fitness, body composition, and physiologic parameters across an elite hockey season. The search of 4 large scientific databases (i.e., Embase, PubMed, SPORTDiscus, and Web of Science) yielded 4,049 items, which, after removing duplicates and applying inclusion and exclusion criteria, resulted in 23 published scientific articles to be included in this review. The wide span of literature (1956-2020) made inferences difficult giving the degree to which the game of ice hockey has changed; however, more recent research points to an aerobic deconditioning pattern and increased fatigue throughout the season in a specific group of elite hockey players (i.e., university athletes) while showing that ice hockey can lead to many possible histological adaptations. Ultimately, tracking, identifying, and developing methods to mitigate potential negative longitudinal changes will be imperative to influencing individual and team performance in the later parts of the season.

Load carriage is a necessary burden for tactical athletes. A combination of training modes, including aerobic conditioning and progressive load carriage, may lead to improved performance. The critical speed (CS) concept enables the practitioner to prescribe high-intensity interval training (HIIT) time limits (TLIMs) from a single 3-minute all-out exercise test (3 MT). We sought to examine the effect of a standard load carriage (18.86 kg) on CS and the finite running capacity > CS (D'). A group of trained subjects (age: 26 ± 5 years, height: 181 ± 4 cm, body mass [BM]: 90 ± 14 kg) completed a loaded and unloaded (UL) 3 MT. The CS was reduced by 0.66 ± 0.24 m·s (p < 0.01) in the loaded condition. There was a small nonsignificant increase in D' (21.25 ± 39.53 m, p = 0.07). The higher the % load carriage relative to BM is, the greater decline in CS (r = 0.83, p < 0.01). A revised CS with load carriage from the UL 3 MT may be calculated using: adjusted CS = original CS + ([-0.0638 × %load]) + 0.6982. Our results indicate that revised CS and TLIMs for fixed distance, fixed time, or fixed speed HIIT prescriptions may be derived from a UL 3 MT. Such calculations would enable more expeditious training for tactical athletes. We recommend further research involving implementation of HIIT using this new method.

To effectively develop physical parameters, training intensities should be individualized to suit an athlete's current fitness level, for example, percentage of 1 repetition maximum in strength and power development. Regarding anaerobic or aerobic conditioning, a velocity prescription can be both accurate and effective in individualizing energy system development. However, there is a sparsity of research available comparing the range of tests capable of determining an appropriate velocity. The following review discusses the optimum way to determine an individual's desired training velocity through field-based testing.

This study aimed to compare the biochemical markers of muscle and liver injury and total antioxidant capacity in army cadets after a traditional army physical training program and to correlate these effects with aerobic conditioning. Male army cadets (n = 87; age, 20 ± 2 years) were evaluated 12 hours before the start of training (T0), 12 hours after a 30-km march (T1), and 48 hours after military training (T2). Creatine kinase (CK), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) serum levels were measured using an autoanalyzer. Total antioxidant capacity was determined by 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (Sc%). Seventy-four percent of army cadets were classified as having excellent aerobic conditioning (53.9 ± 3.0 ml · kg(-) · min(-1) predicted VO2max from the Cooper test). The median serum concentration of all enzymes increased 12 hours after marching (T1: CK 675%; ALT 59%; AST 336%; AST/ALT ratio 85%; p = 0.001) and 48 hours after the end of training (T2: CK 878%; ALT 256%; AST 418%; AST/ALT ratio 180%; p = 0.001). Sc% was higher in T2 (31.1 ± 9.8%; p = 0.01) than in T0 (3.4% change). Maximal oxygen consumption (ml · kg(-1) · min(-1)) correlated negatively with CK (r = -0.25; p = 0.009) and ALT (r = -0.21; p = 0.03) serum levels, and positively with the change in Sc% (r = 0.22; p = 0.04) at T2. The results indicate that intense military training can cause liver and muscle injury and that aerobic conditioning can be considered as a protective factor for these injuries.

The stress of operational missions may challenge the maintenance of body homeostasis, affecting soldiers' cardiac autonomic control, promoting dehydration, and compromising performance. Therefore, we aimed to determine the effects of peacekeeper patrol operation in Haiti on soldiers' hydration status and cardiac autonomic modulation, and to determine whether fluctuations in autonomic modulation were associated with changes in hydration status, energy expenditure (EE), and aerobic fitness (V[Combining Dot Above]O2max). A group of 20 soldiers (23.5 ± 4.7 years; V[Combining Dot Above]O2max 52.9 ± 4.5 ml·kg⁻¹·min⁻¹) completed an operational patrol mission with a mean duration of 160.6 ± 28.6 minutes. Before (Pre) and after (Post) the operation, the soldiers' body masses (BMs) were measured and 5-minute heart rate interbeat (R-R) intervals were recorded at rest to estimate heart rate variability (low-frequency [LF] and high-frequency [HF] power, and sympathovagal balance [LF/HF]). During the mission, EE was estimated using heart rate (HR) monitors. Changes from Pre to Post in BM (%BM loss) and LF/HF (ΔLF/HF) were used to evaluate the soldiers' dehydration levels and autonomic modulation, respectively. The mean EE was 711.0 ± 208.7 kcal. From pre to post, increases (p < 0.01) were noted in LF normalized units (n.u.) and LF/HF and decreases (p < 0.01) were noted in BM, R-R interval, and HF n.u. The variation in ΔLF/HF correlated with EE (r = 0.49; p = 0.02), V[Combining Dot Above]O2max (r = -0.42; p = 0.05), and %BM loss (r = 0.53; p = 0.02). The results demonstrated that an operational peacekeeper patrol with an approximate duration of 160 minutes promoted both dehydration and an imbalance in the autonomic modulation of soldiers' HR. The reduction in sympathovagal balance correlated with EE, dehydration, and aerobic conditioning.

Objective: We examined the effect of aerobic exercise in patients with spinal and bulbar muscular atrophy (SBMA). SBMA is caused by a defect androgen receptor. This defect causes motor neuron death, but considering the important function of androgens in muscle, it is possible that muscle damage in SBMA also occurs independently of motor neuron damage. Methods: Eight patients with SBMA engaged in regular cycling exercise for 12 weeks. Maximum oxygen uptake (Vo 2max ), maximal work capacity (W max ), muscle morphology, citrate synthase (CS) activity, body composition, EMG, static strength measurements, lung function, plasma proteins, and hormones were evaluated before and after training. Evaluation of improvements in activities of daily living (ADL) was conducted after training. Results: W max increased by 18%, and CS activity increased by 35%. There was no significant change in Vo 2max or any of the other variables examined before and after training, and the patients with SBMA did not feel improvements in ADL. Conclusions: Frequent, moderate-intensity aerobic conditioning is of little beneficial effect in patients with spinal and bulbar muscular atrophy (SBMA). High levels of plasma creatine kinase and muscle regeneration indicate a primary myopathic affection, which, in parallel with the motor neuron deficiency, may attenuate the response to exercise training in patients with SBMA.

Purpose: To determine the prevalence and predictors of preseason conditioning among high school athletes. Methods: Cross-sectional survey of 451 high school athletes participating on girls and boys track and boys soccer teams in five public high schools in Seattle, WA, spring 2005. Questions were modified from validated surveys of physical activity for adolescents. The main outcome measure was meeting criteria for adequate preseason conditioning, which specify a combination of aerobic conditioning (vigorous exercise for at least 300 min·wk-1) and stretching and strengthening exercises (at least three times a week for any duration). Log-binomial regression was performed to examine factors associated with preseason conditioning. Results: The majority of athletes met the criteria for each of the components (59% for aerobic conditioning, 62% for stretching, 63% for strengthening). As defined by meeting the criteria for all three components, 33% of the athletes had adequate preseason conditioning. Of those athletes meeting criteria for all three components, the majority reported at least 1 month of conditioning to prepare for the season. Varsity athletes were more likely to meet the preseason conditioning criteria compared with junior varsity athletes (38 vs 25%, prevalence ratio 1.5, 95% CI 1.0-2.1). Athletes who reported help with conditioning from a coach were twice as likely to have adequate preseason conditioning compared with those who did not receive help from a coach (45 vs 23%, prevalence ratio 1.8, 95% CI 1.3-2.4). Conclusion: The majority of athletes in this study did meet criteria for each individual conditioning component (aerobic, stretching, strengthening), but only a minority met all three criteria. These findings highlight the need for school- or coach-sponsored involvement to ensure that all athletes engage in comprehensive preseason conditioning programs.

Roy, J.L.P., K.S. Menear, M.M.A. Schmid, G.R. Hunter, and L.A. Malone. Physiological responses of skilled players during a competitive wheelchair tennis match. J. Strength Cond. Res. 20(3):665-671. 2006.-The purpose of this study was to determine heart rate (HR, b·min?1) response during competitive match play of 6 men who were skilled wheelchair (WC) tennis players. Each participant completed an arm crank ergometer test that measured HR via a telemetry device and O2 via open circuit spirometry from rest until fatigue ( O2peak). Each athlete participated in 2 competitive singles matches during which HRs were recorded in 5-second intervals and O2 was estimated using the corresponding HR values recorded during the arm ergometer tests. Data analysis revealed an average playing intensity of 69.4 ± 8.9% of HRpeak and 49.9 ± 14.5% of O2peak. In conclusion, it is recommended that skilled adult WC tennis players perform off-court aerobic conditioning as part of their training program, because the intensity of a competitive WC tennis match is sufficiently high enough to stress the cardiovascular system.

Purpose This study examined the feasibility, safety, and effectiveness of a community-based group fitness program for children with disabilities. Methods Twenty-eight children with neuromuscular and developmental disabilities, 6 to 14 years of age, participated. The 16-week community-based program, held twice weekly, consisted of strengthening, aerobic conditioning, and flexibility exercises. A pretest-posttest design was used, and the following outcomes were measured: isometric muscle strength of the knee extensors, hip abductors, and ankle plantarflexors, walking energy expenditure, functional mobility, and fitness. Falls and injury data also were collected. Results Mean program attendance was 75.3%, and no injuries were reported. Improvements in all clinical outcomes were observed. The most clinically meaningful improvement was in functional mobility with a large effect size (0.87). Conclusions Physical therapists partnering with community centers may feasibly and safely shift group fitness programs for school-aged children with disabilities from the medical setting to the community.

To this point in time, acupuncture has been used primarily as an analgesic, a therapeutic intervention that controls pain under pathological conditions. Although some of the mechanisms of acupuncture as it applies to pain relief have been studied, little is known of the positive and/or negative effects of this procedure on the physical performance parameters of healthy people, particularly highly trained athletes. After introducing acupuncture from historical and technique viewpoints, preliminary studies of the effects of acupuncture on strength, aerobic conditioning, flexibility, and sport performance are discussed, as well as concerns regarding the direction of research investigating the potential benefit and/ or adverse effects of this practice. Finally, an argument is put forward for the establishment of guidelines for the use of acupuncture in the sports community.

This study examined the effects of advancing gestational age and maternal aerobic conditioning (stationary cycling) on fetal heart rate (FHR) responses to strenuous non-steady-state maternal exercise.Subjects chose to participate in either an exercise group (EG) or control group (CG). Fourteen healthy, previously sedentary pregnant women participated in the exercise group, and six pregnant controls remained sedentary. Stationary cycling (heart rate target: 145 beats x min(-1)) was performed 3 d x wk(-1) by the exercised group. Exercise duration was increased from 14 to 25 min x session(-1) during the second trimester and was maintained at 25 min x session(-1) throughout the third trimester. FHR was monitored before, during, and after a progressive submaximal cycle ergometer test (peak heart rate = 170 beats x min(-1)) performed at approximately 27 and 37 wk gestation.Mean FHR increased significantly (P0.05) during exercise, followed by a modest suppression and then a delayed rise during the recovery period at both observation times. Fetal bradycardia was not observed in any of the exercise tests. Effects of advancing gestational age included a lower FHR baseline both at rest and in response to maternal exercise and a lower incidence of exercise-induced tachycardia. Maternal physical conditioning did not significantly alter FHR response to maternal exercise.Our results support the hypothesis that FHR responses to strenuous exercise are altered by advancing gestational age and a brief progressive exercise test terminated at a maternal heart rate of 170 beats x min(-1) does not induce fetal distress during a healthy pregnancy.

The purpose of this study was to determine the effect of high and low intensity exercise conditioning programs on components pertinent to blood fibrinolysis and selected lipid profile variables in sedentary, but healthy individuals. Eighteen normal subjects were divided into two equal groups: high intensity, and low intensity exercise groups. Each subject in the high and low intensity groups exercised on a bicycle ergometer for 20 min, three times a week for 12 weeks at an intensity corresponding to 80% and 30% VO2 max, respectively. One week before and 1 week after the conditioning programs data were collected for body weight, percentage body fat, VO2 max and 12 h fasting blood levels of total tissue-type plasminogen activator (t-PA), tissue-type plasminogen activator activity (t-PAa), total plasminogen activator inhibitor (PAI-1), plasminogen activator inhibitor activity (PAI-1a), cholesterol (CHOL), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C). Post-conditioning, maximum oxygen consumption increased significantly (P0.05) only in the high intensity exercise group while body weight and percentage body fat did not change (P0.05) in either of the groups. Physical conditioning induced no statistically significant (P0.05) changes in the resting baseline of CHOL, TG or HDL-C. The resting baseline values of t-PA, t-PAa, PAI-1 and PAI-1a before conditioning did not vary significantly (P0.05) between two groups. Similarly, after training no significant change in t-PA, t-PAa or PAI-1. However, PAI-1a decreased significantly (P0.05) in the high intensity group, but not in the low intensity (P0.05). It is concluded that high, but not low, intensity physical conditioning significantly enhances the cardiorespiratory fitness and reduces the resting level of plasminogen activator inhibitor activity which may be linked with the favourable effects of exercise conditioning.

PURPOSE The convalescent period after myocardial infarction (MI) has been associated with a "spontaneous" improvement in functional aerobic capacity that may be because of normal recovery processes unrelated to formal exercise training. The purpose of this study was to determine whether the frequency of formal training sessions is an important variable affecting the magnitude of improvement in cardiorespiratory fitness during phase II cardiac rehabilitation. METHODS The effect of exercise training frequency on cardiorespiratory fitness was evaluated during a 5-week early (phase II) cardiac rehabilitation program in 50 low-risk, male patients recovering from acute MI. Baseline graded treadmill tests to fatigue endpoints, with direct measurement of maximal oxygen uptake (VO2max), were administered 4 weeks after MI. The subjects were then randomly assigned to either a control group (n = 12) and restricted to "very light" physical activity (requiring < 50% of VO2max) at home, or to one of three training groups which, in addition to very light home activity, performed moderately intense (approximately 70% of VO2max) aerobic exercise for 30 to 35 minutes either once per week (n = 13), twice per week (n = 13), or three times per week (n = 12) in the hospital-based phase II program. The four groups were similar in age, clinical status, and use of beta- and calcium channel blockers. RESULTS Submaximal and maximal cardiorespiratory responses were initially similar in all four groups. Each of the four groups demonstrated significant (P < .05) increases in maximal treadmill duration at follow-up. However, VO2max increased significantly only in the three training groups. The spontaneous improvement in treadmill duration in the control group, in the absence of formal exercise training, may simply reflect recovery from the acute cardiac event. Those training two and three sessions per week also showed significant, comparable decreases in submaximal exercise heart rate and rate-pressure product and similar increases in maximal treadmill duration and VO2max. CONCLUSIONS Results suggest that two exercise sessions per week is as effective as three per week for cardiorespiratory conditioning in the early weeks of phase II cardiac rehabilitation.

Purpose of review Although prolongation of life is a significant public health aim, at the same time the extended life should involve preservation of the capacity to live independently. Consequently, the identification of cost-effectiveness interventions to prevent frailty is one of the most important public health challenges. In the present review, we present the available evidence regarding the impact of physical exercise on the components of frailty syndrome and, in particular, as a remedy for sarcopenia. Recent findings Resistance exercise training is more effective in increasing muscle mass and strength, whereas endurance exercises training is superior for maintaining and improving maximum aerobic power. Based on these evidences, recommendations for adult and frail older people should include a balanced program of both endurance and strength exercises, performed on a regular schedule (at least 3 days a week). Summary Regular exercise is the only strategy found to consistently prevent frailty and improve sarcopenia and physical function in older adults. Physical exercises increase aerobic capacity, muscle strength and endurance, by ameliorating aerobic conditioning and/or strength. In older patients, exercise and physical activity produce at least the same beneficial effects observed in younger individuals.

Snowshoeing is currently ranked as one of the top 20 participatory sports in the United States, and the number of participants almost tripled, from 440,000 to 1.2 million in 1998. Despite this large increase in participation, no scientific evidence exists to quantify any physiologic response to the activity. Therefore, the purpose of this investigation was to assess the energy expenditure of snowshoeing at selected low-level speeds and evaluate its acceptability as a form of aerobic conditioning exercise. Ten habitually active subjects (7 men, 3 women, mean age = 24 +/- 3.9 years, mass = 76.6 +/- 14.5 kg, height = 173.7 +/- 9.6 cm) were recruited. Steady state heart rate data were determined from 2 treadmill tests at 4 and 6 mph. Steady state heart rates at 4 mph and 6 mph from treadmill speeds were then reproduced outdoors under 2 snow conditions, packed, and unpacked snow, while caloric expenditure and speed were determined. Expired gases were collected in Douglas bags for both snowshoe and treadmill trials and then analyzed and corrected indoors for the fractional concentrations of carbon dioxide and oxygen. Data analyses indicate that caloric expenditure during snowshoeing may be considerably higher than previously reported. Snowshoeing on packed snow at 2.95 mph elicited a similar heart rate and energy expenditure response as walking on a treadmill at 4 mph or snowshoeing in unpacked snow at 2.04 mph (Vo(2) = 18.18 +/- 0.8 ml x kg(-1) x min(-1)). Snowshoeing on packed snow at 3.97 mph elicited the same heart rate and energy expenditure response as walking on a treadmill at 6 mph or snowshoeing on unpacked snow at 2.87 mph (Vo(2) = 36.72 +/- 0.8 ml x kg(-1) x min(-1)). Furthermore, increasing walking speed on snow by just 1 mph at slow speeds (2 and 3 mph) resulted in approximately twice the energy expenditure. Our data indicate that current estimates of energy expenditure while snowshoeing underestimate by greater than 50%. Apparently the energy expenditure during snowshoeing is much higher than previously considered and varies considerably because of snow terrain. Furthermore, energy expenditure levels similar to walking can be achieved on snowshoes at much slower speeds. This study represents an original investigation into energy expenditure during snowshoeing.

Weight training is believed to result in little cardiovascular benefit compared to aerobic conditioning. In this study, heart rate and blood pressure changes in previously sedentary men were observed at rest and during simulated daily physical activities before and after a controlled 16-week conditioning program of either weight training or running. Body composition, peak oxygen uptake (JOURNAL/jscr/beta/00124278-199411000-00003/ENTITY_OV0312/v/2017-05-04T192910Z/r/image-pngO2peak), and strength were assessed before and after the study. At rest, during isometric exertion, and while performing two levels of treadmill walking, runners and weight trainers had lower estimates of myocardial oxygen consumption compared to controls. After training, both runners and weight trainers decreased their percent body fat. JOURNAL/jscr/beta/00124278-199411000-00003/ENTITY_OV0312/v/2017-05-04T192910Z/r/image-pngO2,peak was increased among runners, while only the weight trainers increased strength. These effects are comparable to aerobic exercise during isometric and mixed isometric and dynamic activities, and can occur without enhancement of peak oxygen uptake.

The findings in ten subjects who had an amputation of the lower limb or limbs were studied before and after a fifteen-week aerobic conditioning program to determine if it improved cardiovascular fitness and reduced the effort of walking. Each subject exercised on an Air-Dyne ergometer (Schwinn, Chicago, Illinois) regularly during each week of the study period at 60 to 80 per cent of their estimated maximum heart rate. A test of maximum exercise on the ergometer and a test of walking on a treadmill were administered before and after training. After training, there was an increase of 25 per cent in the maximum capacity for exercise on the ergometer as well as significantly lower values for heart rate and consumption of oxygen during submaximum walking on the treadmill at various inclined grades. Aerobic conditioning was shown not only to improve cardiovascular fitness but also to increase the economy of walking in the subject who had an amputation of the lower limb or limbs.

This study investigated the potential value of specific cellular responses to acute and chronic exercise as indices of physical fitness. Muscle enzymatic and hemolytic responses following a progressive cycle-ergometer test to maximal aerobic capacity were studied in 12 women and 12 men, aged 27 to 55 yr, who had been previously assigned to "high" and "low" fitness groups. Venous blood samples were obtained at rest prior to the cycle test, immediately following maximal effort, and 1, 2, 4, 6 and 24 h post exercise. The samples were analyzed for hematocrit (Hct), hemoglobin (Hb), lactate dehydrogenase (LDH), serum glutamic oxalacetic transaminase (SGOT), creatine phosphokinase (CK), CK isoenzymes, and haptoglobin (Hapt). Hemoglobin and Hct were the only variables to rise significantly (P less than 0.05) following exercise, and at all sampling times were significantly lower in the women compared with the men; CK was constituted in the MM isoenzyme band at all times; and Hapt levels were significantly lower in high-fitness men and women as compared with low-fitness men and women. These results indicate that one progressive test to maximal aerobic capacity is not sufficient to induce significant muscle enzymatic or hemolytic stress responses. They do suggest, however, that a chronic hemolytic condition exists as a result of aerobic conditioning activity.

It is often recommended that during exercise the exerciser monitor his heart rate so that it can be maintained at a rate rapid enough to promote aerobic conditioning but not so rapid as to be dangerous. Various authorities recommend that the heart rate be determined by placing the fingers al

Nineteen fit college-age men were studied using foot (mid-arch) mercury-in-silastic strain gauge plethysmography before and after an 8-wk aerobic conditioning (running) program. Foot volume changes were followed through two maneuvers: a 15-s Trendelenburg procedure (passive leg elevation with subsequent relaxation in the dependent position) and a 15-s dynamic dorsi-flexion/plantar flexion exercise and subsequent relaxation. The conditioning regimen consisted of running 40 min, 3 d.wk-1 and resulted in a 10% (P less than 0.01) increase in VO2max. Following this regimen, subjects exhibited an increased blood volume drainage during the Trendelenburg procedure (mean delta VT = 3.3 ml.100 ml-1 pre-training, 3.8 ml.100 ml-1 post-training, P less than 0.05), but no significant change in delta VE (2.7 ml.100 ml-1 for all subjects). Muscle pump efficacy, defined as the ratio between delta VE and delta VT, did not change (64%). These data suggest that increased aerobic power via weight-bearing exercise training results in an increased foot venous pooling, but does not affect relative muscle pump function. This apparent increase in vascular pooling may be a physical response to the hypervolemia induced by endurance training, aiding in maintaining the constancy of vascular pressures.

M.M. COWAN and L.W. GREGORY. Responses of pre- and post-menopausal females to aerobic conditioning. Med. Sci. Sports Exerc. Vol. 17, No. 1, pp. 138–143, 1985. This study sought to determine whether the ability to improve cardiorespiratory endurance and body composition is affected by the menopausal status of females. Twenty premenopausal females and 18 postmenopausal females, ages 35–49 and 47–66 yr, respectively, were randomly assigned to exercise and control groups depending on menopausal status. Both exercise groups (PRE-EX, N = 16; POST-EX, N = 14) participated in a progressive walking program (4 days/week for 9 weeks) at an intensity of 80% the age-adjusted heart rate maximum (80% HRM). Following training, both exercise groups significantly improved submaximal exercise capacity (SEC) as measured by oxygen consumption (l/min; ml/kg-min) and treadmill walking time at 80% HRM. The PRE-EX group significantly improved percent body fat and lean body weight, while there was no significant change in total body weight. The POST-EX group significantly improved total body weight and percent body fat with no significant change in lean body weight. Although some of these changes in body composition were statistically significant, overall the alterations were minimal. ANCOVA revealed exercise, not menopause, to be the effective treatment for improving percent body fat and SEC80%HRM. There were no significant differences between the PRE-EX and POST-EX groups in their ability to improve SEC80%HRM or to reduce percent body fat. The POST-EX group had a significantly greater reduction in total body weight, while the PRE-EX group had significantly greater increases in lean body weight. These findings suggest that the ability to favorably alter body composition and cardiorespiratory endurance through the aerobic conditioning of females is independent of menopausal status.

The purpose of this study was to compare the effects of exercise and/or caloric restriction for 12 wk on body composition, maximal aerobic power (VO2max), and serum lipids and lipoproteins in overweight individuals. Forty-eight males and 48 females (means age = 36.6 yr), 120-140% of ideal body weight, were randomly assigned to groups (N = 12 each) of diet-exercise (DE), diet (D), exercise (E), and sedentary control (C). The dietary regimen consisted of 1,200 kcal X d-1, while exercise consisted of 5 d X wk-1 of 30 min of walk/running. For the males, body weight (BW) and fat weight loss in the DE group (-11.8 and 23%, respectively) were significantly greater than in the D group (-9.1 and -18%), with both groups significantly greater than for E and C. In the females, BW and fat weight loss for DE (-10.4 and -24%) were significantly greater than for D (-7.8 and -20%), with both groups significantly greater than E and C. Both DE and D males and females had a decrease in fat-free weight of -4.5 and -2.4%, respectively. In both sexes, the increase in VO2max-BW (ml X kg -1 X min-1) in DE (25%) was significantly greater than for E (15%), D (11%), and C (0%), with differences between E and D nonsignificant. However, increases in absolute VO2max (1 X min-1) and VO2max-fat-free weight (ml X kg-1 X min-1) were similar (P greater than 0.05) for DE and E (14%) but significantly greater compared to D and C (2%).(ABSTRACT TRUNCATED AT 250 WORDS)

Skiing requires aerobic fitness. For aerobic conditioning, there must be significant elevation in heart rate during training. Although anaerobic training benefits physical fitness in general, skiing requires more aerobic than anaerobic conditioning. Strength, power, and endurance can be maintained through the use of concentric and eccentric contractions, using a variety of equipment and sports. Care should be taken to avoid injury to the patellofemoral joint during training. It is important to use specificity in choosing sports, as well as the exercise patterns in preseason training. If these principles are recognized in ski conditioning, a successful and effective training program will result.

A paucity of information exists concerning the exact role of exercise in the management of low back pain. Few controlled clinical studies exist, and the selection of an exercise program is often relegated to traditional or empiric regimens. Aerobic conditioning exercises appear to offer the greatest benefit for all types of patients with back problems, although the value of these exercises is often overstated. Indirect evidence can be found for strengthening exercises that treat physical incapacity. No information is available to substantiate effects on pain relief. Comprehensive electromyographic studies, biomechanical analyses, and controlled clinical studies are needed to validate the role of exercises in the treatment of patients with back pain.