Effects of body fat and dominant somatotype on explosive strength and aerobic capacity trainability in prepubescent children.

The purpose of this study was to analyze the influence of body fat and somatotype on explosive strength and aerobic capacity trainability in the prepubertal growth spurt, marked by rapid changes in body size, shape, and composition, all of which are sexually dimorphic. One hundred twenty-five healthy children (58 boys, 67 girls), aged 10-11 years (10.8 ± 0.4 years), who were self-assessed in Tanner stages 1-2, were randomly assigned into 2 experimental groups to train twice a week for 8 weeks: strength training group (19 boys, 22 girls), endurance training group (21 boys, 24 girls), and a control group (18 boys, 21 girls). Evaluation of body fat was carried out using the method described by Slaughter. Somatotype was computed according to the Heath-Carter method. Increased endomorphy reduced the likelihood of vertical jump height improvement (odds ratio [OR], 0.10; 95% confidence interval [CI], 0.01-0.85), increased mesomorphy (OR, 6.15; 95% CI, 1.52-24.88) and ectomorphy (OR, 6.52; 95% CI, 1.71-24.91) increased the likelihood of sprint performance, and increased ectomorphy (OR, 3.84; 95% CI, 1.20-12.27) increased the likelihood of aerobic fitness gains. Sex did not affect the training-induced changes in strength or aerobic fitness. These data suggest that somatotype has an effect on explosive strength and aerobic capacity trainability, which should not be disregarded. The effect of adiposity on explosive strength, musculoskeletal magnitude on running speed, and relative linearity on running speed and aerobic capacity seem to be crucial factors related to training-induced gains in prepubescent boys and girls.

The influence of the level of physical activity and human development in the quality of life in survivors of stroke.

BACKGROUND: The association between physical activity and quality of life in stroke survivors has not been analyzed within a framework related to the human development index. This study aimed to identify differences in physical activity level and in the quality of life of stroke survivors in two cities differing in economic aspects of the human development index. METHODS: Two groups of subjects who had suffered a stroke at least a year prior to testing and showed hemiplegia or hemiparesis were studied: a group from Belo Horizonte (BH) with 48 people (51.5 ± 8.7 years) and one from Montes Claros (MC) with 29 subjects (55.4 ± 8.1 years). Subsequently, regardless of location, the groups were divided into Active and Insufficiently Active so their difference in terms of quality of life could be analyzed. RESULTS: There were no significant differences between BH and MCG when it came to four dimensions of physical health that were evaluated (physical functioning, physical aspect, pain and health status) or in the following four dimensions of mental health status (vitality, social aspect, emotional aspect and mental health). However, significantly higher mean values were found in Active when compared with Insufficiently Active individuals in various measures of physical health (physical functioning 56.2 ± 4.4 vs. 47.4 ± 6.9; physical aspect 66.5 ± 6.5 vs. 59.1 ± 6.7; pain 55.9 ± 6.2 vs. 47.7 ± 6.0; health status 67.2 ± 4.2 vs. 56.6 ± 7.8) (arbitrary units), and mental health (vitality 60.9 ± 6.8 vs. 54.1 ± 7.2; social aspect 60.4 ± 7.1 vs. 54.2 ± 7.4; emotional aspect 64.0 ± 5.5 vs. 58.1 ± 6.9; mental health status 66.2 ± 5.5 vs. 58.4 ± 7.5) (arbitrary units). CONCLUSIONS: Despite the difference between the cities concerning HDI values, no significant differences in quality of life were found between BH and MCG. However, the Active group showed significantly better results, confirming the importance of active lifestyle to enhance quality of life in stroke survivors.

Correction: Are wearable heart rate measurements accurate to estimate aerobic energy cost during low-intensity resistance exercise?

[This corrects the article DOI: 10.1371/journal.pone.0221284.].

Effects of Ibuprofen Intake in Muscle Damage, Body Temperature and Muscle Power in Paralympic Powerlifting Athletes.

The aim of this study is to evaluate the effect of ingesting ibuprofen on post-workout recovery of muscle damage, body temperature and muscle power indicators in Paralympic powerlifting athletes. The study was carried out with eight Paralympic powerlifting athletes (aged 27.0 ± 5.3 years and 79.9 ± 25.5 kg of body mass) competing at the national level, with a minimum training experience of 12 months, who all submitted to two experimental conditions: Ibuprofen (2 × 00 mg) and control. The maximal isometric force of the upper limbs and rate of force development, thermography, and serum biochemical analyzes of creatine kinase, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were measured before, after, 24 h after and 48 h after the intervention. Maximal isometric force only decreased in the placebo condition, which increased back to baseline levels, while no substantial decline in baseline force was seen in the ibuprofen condition, although no effect for exercise condition was detected. After the exercise, the rate of force development decreased significantly for both conditions and did not exceed baseline levels again after 48 h. Muscle temperature decreased significantly at 48-h post-exercise in the placebo condition, when compared with the previous day of measurement; and deltoid muscle temperature at 48-h post-exercise was higher with the ibuprofen condition. Although the results indicate some positive effects of ibuprofen use, they do not enable a clear statement regarding its positive effects on muscle function and muscle damage. Ibuprofen seems to have caused a delay in the anti-inflammatory response following exercise.

Oxygen Uptake On-Kinetics during Low-Intensity Resistance Exercise: Effect of Exercise Mode and Load.

Oxygen uptake (VO2) kinetics has been analyzed through mathematical modeling of constant work-rate exercise, however, the exponential nature of the VO2 response in resistance exercise is currently unknown. The present work assessed the VO2 on-kinetics during two different sub maximal intensities in the inclined bench press and in the seated leg extension exercise. Twelve males (age: 27.2 ± 4.3 years, height: 177 ± 5 cm, body mass: 79.0 ± 10.6 kg and estimated body fat: 11.4 ± 4.1%) involved in recreational resistance exercise randomly performed 4-min transitions from rest to 12% and 24% of 1 repetition maximum each, of inclined bench press (45°) and leg extension exercises. During all testing, expired gases were collected breath-by-breath with a portable gas analyzer (K4b2, Cosmed, Italy) and VO2 on-kinetics were identified using a multi-exponential mathematical model. Leg extension exercise exhibited a higher R-square, compared with inclined bench press, but no differences were found in-between exercises for the VO2 kinetics parameters. VO2 on-kinetics seems to be more sensitive to muscle related parameters (upper vs. lower body exercise) and less to small load variations in the resistance exercise. The absence of a true slow component indicates that is possible to calculate low-intensity resistance exercise energy cost based solely on VO2 measurements.

Are wearable heart rate measurements accurate to estimate aerobic energy cost during low-intensity resistance exercise?

The aim of the present study was to assess the accuracy of heart rate to estimate energy cost during eight resistance exercises performed at low intensities: half squat, 45° inclined leg press, leg extension, horizontal bench press, 45° inclined bench press, lat pull down, triceps extension and biceps curl. 56 males (27.5 ± 4.9 years, 1.78 ± 0.06 m height, 78.67 ± 10.7 kg body mass and 11.4 ± 4.1% estimated body fat) were randomly divided into four groups of 14 subjects each. Two exercises were randomly assigned to each group and subjects performed four bouts of 4-min constant-intensity at each assigned exercise: 12%, 16%, 20% and 24% 1-RM. Exercise and intensity order were random. Each subject performed no more than 2 bouts in the same testing session. A minimum recovery of 24h was kept between sessions. During testing VO2 was measured with Cosmed K4b2 and heart rate was measured with Polar V800 monitor. Energy cost was calculated from mean VO2 during the last 30-s of each bout by using the energy equivalent 1 ml O2 = 5 calorie. Linear regressions with heart rate as predictor and energy cost as dependent variable were build using mean data from all subjects. Robustness of the regression lines was given by the scatter around the regression line (Sy.x) and Bland-Altman plots confirmed the agreement between measured and estimated energy costs. Significance level was set at p≤0.05. The regressions between heart rate and energy cost in the eight exercises were significant (p<0.01) and robustness was: half squat (Sy.x = 0,48 kcal·min-1), 45° inclined leg press (Sy.x = 0,54 kcal·min-1), leg extension (Sy.x = 0,59 kcal·min-1), horizontal bench press (Sy.x = 0,47 kcal·min-1), 45° inclined bench press (Sy.x = 0,54 kcal·min-1), lat pull down (Sy.x = 0,28 kcal·min-1), triceps extension (Sy.x = 0,08 kcal·min-1) and biceps curl (Sy.x = 0,13 kcal·min-1). We conclude that during low-intensity resistance exercises it is possible to estimate aerobic energy cost by wearable heart rate monitors with errors below 10% in healthy young trained males.

Influence of aquatic exercises in physical condition in patients with multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a disabling chronic disease of the nervous system in which the myelin system of the central nervous system is deteriorated. This study aimed to evaluate the effectiveness of an aquatic exercise program on the physical condition of patients suffering from multiple sclerosis. METHODS: The study included 26 participants divided into two groups: an experimental group (EG) with 13 individuals and a control group (CG) also with 13 individuals. The EG underwent 12 weeks of aquatic exercise, three times per week and 45-60 minutes per session. The groups were evaluated pre- and post-intervention, and were later compared to check for differences between groups. Data was collected by using functional tests such as the Timed "Up and Go" Test, the Timed 7.62 Meters Walk Test, the Getting up from a Sitting Position Test and the Balance Test. RESULTS: Significant differences were found between the groups in the post-intervention stage. Furthermore, significant differences were also observed in all domains of physical condition of EG patients, in the post-intervention stage. Results obtained from the intention-to-treat analysis were consistent with those found in the literature. CONCLUSIONS: Therefore, this study's results suggest that aquatic exercise programs can effectively improve multiple sclerosis patient's physical condition and should be considered when coping with this public health problem.

A randomized trial of the effects of an aquatic exercise program on depression, anxiety levels, and functional capacity of people who suffered an ischemic stroke.

BACKGROUND: Aquatic exercise programs are used in rehabilitation and might help to reduce disability after stroke. This was a randomized intervention trial to assess the influence of an aquatic exercise program on people suffering from depression and anxiety after ischemic stroke. METHODS: Participants were randomized to an experimental group (EG) composed of 19 individuals (51.8±8.5 years; ten males and nine females), and a control group (CG) composed of 17 people (52.7±6.7 years; nine males and eight females). The aquatic exercise program consisted of two sessions per week, each lasting between 45 and 60 minutes and divided into 5 to 10 minutes exercise sections during 12 weeks. The State-Trait Anxiety Inventory was used to determine anxiety levels while the Beck Depression Inventory was used as a self-assessment of depression. RESULTS: EG improved measures of depression, anxiety trait and anxiety state between pre- and post-treatment, with no changes in CG. EG improved in all tests related to functional capacity compared to CG. CONCLUSIONS: The practice of aquatic exercises promotes improvements in the levels of depression and anxiety in people who suffered an ischemic stroke.

Effects of resistance training on the physical condition of people with multiple sclerosis.

BACKGROUND: This study aimed to evaluate the effect of resistance training on the functional capacity of people with multiple sclerosis. Two groups were defined intentionally and divided based on the Expanded Disability Status Scale (EDSS): an experimental group (EG) consisting of 11 individuals, 18.2% with an EDSS Score of 0-3.0, 72.8% with a score of 3.5-5.5 and 9.1% with a score of 6.0-7.5; and a control group (CG) consisting of 12 subjects, 25.0% with a score of 0-3.0, 58.3% with a score of 3.5-5.5 and 16.7% with a score of 6.0-7.5. METHODS: The EG underwent 12 weeks of resistance training, while the CG did not. The Timed "Up & Go" test was used to measure the function of the lower limbs. The Timed 7.62 Meters Walk test and the Sit-to-stand test were used to assess the strength of the lower limbs. Balance, and the risk of falling, were assessed through the Berg Balance Test. RESULTS: At the beginning of the study, there were no differences between EG and CG in lower limb function. However, after the 12 weeks of resistance training, significant differences were found between the EG and the CG in the Timed "Up and Go" test (P=0.021), Timed 7.62 Meters Walk (P=0.027), Sit-to-stand (P=0.017) and Balance test (P=0.039). CONCLUSIONS: This study's results indicate that this type of training can improve muscle strength and functional capacity in patients with multiple sclerosis.