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Purpose: We examined the effects of aerobic exercise and detraining on adiponectin, resistin, tumor necrosis factor alpha (TNF-α), white blood cell, and pubertal signs (uterine length, ovarian volume, luteinizing hormone [LH], and follicle-stimulating hormone [FSH]) in girls with central precocious puberty (CPP). Methods: Thirty girls with CPP (7–9 yr old) were randomly divided into CPP and CPP + Exercise (EX) groups. Fifteen healthy age-matched girls without precocious puberty participated for comparison with CPP. Subjects in the CPP + EX group attended 12 wk of aerobic exercise protocol three sessions a week. In the baseline, after completing the exercise protocol and after 4 wk of detraining, all the parameters were measured. In the CPP and healthy groups, all the parameters were measured in all three stages. To measure adiponectin, resistin, and TNF-α, the ELISA method was used. LH and FSH were measured by electrochemiluminescence immunoassay. White blood cell counts were analyzed by an automated blood cell counter. Repeated-measures ANOVA was used to analyze the results. Results: CPP girls have lower adiponectin (P = 0.01) and higher TNF-α levels (P = 0.001) than healthy girls. In the CPP + EX group, after 12 wk, body weight and fat mass decreased, and adiponectin increased significantly (P = 0.02). Resistin (P = 0.02), TNF-α (P = 0.02), neutrophils (P = 0.01), and signs of puberty significantly (P < 0.05) decreased. After detraining, no significant change was observed except TNF-α, which increased significantly (P = 0.03). In the CPP group, no significant change was observed in any of the parameters; only LH (P = 0.0001) and uterine length and ovarian volume (P = 0.003, P = 0.001) decreased after 12 and 16 wk, respectively. Conclusions: Aerobic exercise can have a positive effect on the state of inflammation and pubertal signs. Positive effects remain after 4 wk of detraining. [ABSTRACT FROM AUTHOR]

Introduction: Multiple sclerosis (MS) is an immune-mediated, neurological disease that results in physiological deconditioning with increasing disability. High-intensity interval training (HIIT) exercise has induced significant improvements in physiological conditioning in healthy and clinical populations and might be appropriate for persons with MS who have mobility disability. The feasibility and acute effects of HIIT using recumbent stepping in persons with MS who have mobility disability are relatively unknown. Methods: The physiological effects of single sessions of HIIT and continuous (CON), steady-state aerobic exercise using recumbent stepping were compared in 20 persons with MS with mobility disability (i.e., Expanded Disability Status Scale of 4.0–6.5). The HIIT bout included 10 cycles of 1-min intervals at the work rate associated with 90% peak aerobic capacity (V˙O2peak) followed by 1-min recovery intervals at 15 W, totaling 20 min in length. The CON bout consisted of 20 min at the work rate associated with 50% to 60% V˙O2peak. Physiological (i.e., power output, oxygen consumption, carbon dioxide expiration, respiratory exchange ratio, ventilation, HR, and core temperature) and perceptual (i.e., ratings of perceived exertion) measures were collected across the acute sessions. Results: There were statistically significant condition–time interactions for all physiological measures and ratings of perceived exertion expressing differential patterns of change over time for HIIT versus CON (P < 0.05). The main effect of condition was significant for all physiological outcomes, except core temperature, with the HIIT condition inducing significantly higher values than CON (P < 0.05). Conclusions: High-intensity interval training exercise taxes the cardiorespiratory system significantly more than CON, yet without deleterious effects on core temperature in persons with MS. This has important implications for informing an evidence-based exercise prescription that is appropriate for improving physiological conditioning in persons with MS who have mobility disabilities. [ABSTRACT FROM AUTHOR]

Supplemental digital content is available in the text. Introduction: This study investigated the safety and effectiveness of a new integrated aerobic and resistance exercise training prescription (SPRINT) using two different sets of exercise equipment: a suite of large International Space Station–like exercise equipment similar to what is found on the International Space Station and a single device with aerobic and resistance exercise capability in the spaceflight analog of bed rest (BR). Methods: Subjects (n = 34) completed 70 d of 6° head down tilt BR: 9 were randomized to remain sedentary (CONT), 9 to exercise training using traditional equipment (EX), 8 to exercise using traditional equipment and low-dose testosterone supplementation (ExT), and 8 to exercise using a combined resistance and aerobic flywheel device. Peak aerobic capacity, ventilatory threshold, cardiac morphology and function (echocardiography), muscle mass (magnetic resonance imaging) and strength/power (isokinetic, leg press, and vertical jump), and bone health (bone mineral density, blood and urine bone markers) were assessed before and after BR. Results: The SPRINT protocol mitigated BR-induced muscle and cardiac deconditioning regardless of the exercise device used. Molecular markers of bone did not change in the CONT or EX groups. Peak aerobic capacity was maintained from pre- to post-BR in all exercise groups similarly, whereas significant declines were observed in the CONT group (~10%). Significant interaction effects between the CONT group and all EX groups were observed for muscle performance including leg press total work, isokinetic upper and lower leg strength, vertical jump power, and maximal jump height as well as muscle size. Conclusions: This is the first trial to evaluate multisystem deconditioning and the role of an integrated exercise countermeasure. These findings have important implications for the design and implementation of exercise-based countermeasures on future long-duration spaceflight missions. [ABSTRACT FROM AUTHOR]

Purpose: Breast cancer-related lymphedema is a common and debilitating side effect of cancer treatment. This randomized trial compared the effect of progressive resistance- or aerobic-based exercise on breast cancer-related lymphedema extent and severity, as well as participants_ muscular strength and endurance, aerobic fitness, body composition, upper-body function, and quality of life.Methods:Women with a clinical diagnosis of stable unilateral, upper-limb lymphedema secondary to breast cancer were randomly allocated to a resistance-based (n = 21) or aerobic- based (n = 20) exercise group (12-wk intervention).Women were assessed preintervention, postintervention, and 12 wk postintervention, with generalized estimating equation models used to compare over time changes in each groups lymphedema (two-tailed P < 0.05). Results: Lymphedema remained stable in both groups (as measured by bioimpedance spectroscopy and circumferences), with no significant differences between groups noted in lymphedema status. There was a significant (P < 0.01) time-group effect for upper-body strength (assessed using four to six repetition maximum bench press), with the resistance-based exercise group increasing strength by 4.2 kg (95% confidence interval [CI] = 3.2-5.2) postintervention compared with 1.2 kg (95% CI =j0.1 to 2.5) in the aerobic-based exercise group. Although not supported statistically, the aerobic-based exercise group reported a clinically relevant decline in number of symptoms postintervention (-1.5, 95% CI = -2.6 to -0.3), and women in both exercise groups experienced clinically meaningful improvements in lower-body endurance, aerobic fitness, and quality of life by 12-wk follow-up. Discussion: Participating in resistance- or aerobic-based exercise did not change lymphedema status but led to clinically relevant improvements in function and quality of life, with findings suggesting that neither mode is superior with respect to lymphedema effect. As such, personal preferences, survivorship concerns, and functional needs are important and relevant considerations when prescribing exercise mode to those with secondary lymphedema. [ABSTRACT FROM AUTHOR]

The article investigates the time-course changes of several commonly used makers of oxidative stress by performing serial measurements during a 24-hour period after an acute bout of strenuous cardiovascular exercise. The results of the study indicate that there is no best time point applying to all makers for collecting blood samples after aerobic exercise. The optimum postexercise time points for blood collection in untrained individuals are immediately after exercise for catalase, 1 hour for thiobarbituric acid-reactive substances, 2 hours for total antioxidant capacity, reduced glutathione and oxidized glutathione while 4 hours after exercise for protein carbonyls.

The article focuses on a study which aims to determine the aerobic fitness' role on central neuromuscular activation and maximal voluntary contractile force with 37 men from aerobic fitness and training history placed in a 35 degrees centigrade environment using liquid garment . The study shows that in production, there was a passive heating attenuated force, decrease in voluntary activation, and moderate increased in cardiovascular strain. In addition, the study concludes that low aerobic fitness and activity level are associated with a decreased tolerance to passive hyperthermia. Furthermore, voluntary and maximum activation during high body temperatures were afflicted regardless of training status to an equal level.

Introduction: Aerobic exercise training has been shown to improve cardiovascular function and lower blood pressure (BP) in older adults. The exact mechanism(s) by which aerobic exercise training elicits these changes are unknown; however, it is possible that changes in renal hemodynamics may play a role. Purpose: The present study was undertaken to examine the effect of aerobic exercise training on renal hemodynamics in older hypertensive individuals. Methods: Renal plasma flow (RPF) and glomerular filtration rate (GFR) were determined by plasma and urinary clearances of 131I-hippuran and 99mTc-DTPA after 8 d of low (20 mEq) and high (200 mEq) Na+ diets in 31 older (63 ± 1 yr), hypertensive (152 ± 2/88 ± 1 mm Hg) individuals at baseline and following 6 months of aerobic exercise training (at 75% ...O2max, three times a week, 40 min per session). Results: Following 6 months of aerobic exercise training, a significant increase was seen in maximal aerobic capacity (...O2max; 18.3 ± 0.7 vs 20.7 ± 0.7 mL·kg-1min-1, P = 0.017) as well as a significant decrease in resting systolic (152 ± 2 vs 145 ± 2 mm Hg, P = 0.037) and mean arterial (109 ± 1 vs 105 ± 1 mm Hg, P = 0.021) BP. No significant (P < 0.05) effects were seen of aerobic exercise training on RPF (208.8 ± 12.2 vs 197.1 ± 13.1 mL·min-1·1.73 m-2), GFR (68.9 ± 3.6 vs 69.0 ± 3.9 mL·min-1·1.73 m-2), or filtration fraction (35.3 ± 2.3 vs 37.1 ± 2.4%) on the low Na+ diet or RPF (210.6 ± 12.8 vs 212.1 ± 11.7 mL·min-1·1.73 m-2), GFR (72.9 ± 4.1 vs 77.3 ± 4.3 mL·min-1·1.73 m-2), or filtration fraction (37.1 ± 2.5 vs 37.7 ± 3.0%) on the high Na+ diet. Conclusions: Our results suggest that changes in renal hemodynamics do not contribute to the reduction in resting BP in older hypertensive persons. [ABSTRACT FROM AUTHOR]

SUMMARY: KETELHUT, R. G., I. W. FRANZ, and J. SCHOLZE. Regular Exercise as an Effective Approach in Antihypertensive Therapy. Med. Sci. Sports Exerc., Vol. 36, No. 1, pp. 4-8, 2004.PURPOSE Exercise has been well documented to exert a beneficial effect on cardiovascular health. The effective control of arterial pressure (BP) is essential from the standpoint of cardiovascular prevention. So far, no study has determined the long-term effect of regular training as a monotherapy on both BP at rest and during exercise.METHODS Therefore, 10 subjects with hypertension (aged 43 ± 3 yr) were studied in order to define BP response to long-term aerobic training. BP measurements were obtained at rest and during ergometry (50-100 W). Patients were instructed to exercise weekly (2 × 60 min aerobic exercise).RESULTS BP during exercise (100 W) did fall already after 6 months of regular training from 184 ± 10/107 ± 6 to 170 ± 10/100 ± 7, and this was associated with a 14% decrease in the rate-pressure product (at 100 W). After 18 months of training, there were further reductions in BP, at rest from 139 ± 9/96 ± 6 to 133 ± 14/91 ± 7 (P < 0.05) and during ergometry (100 W) from 184 ± 10/107 ± 6 to 172 ± 8/96 ± 6 mm Hg (P < 0.001). During a 3-yr follow-up, BP continued to decrease significantly to 130 ± 13/87 ± 7 mm Hg at rest and 167 ± 9/92 ± 6 mm Hg during exercise. No significant changes in body weight were documented during the training period.CONCLUSION The data demonstrate that long-term aerobic exercise is associated with a decrease in BP at rest and during exercise, which is comparable to that of drug therapies. This antihypertensive effect of regular training can be maintained as long as 3 yr. [ABSTRACT FROM AUTHOR]