Recurrence quantification analysis of heart rate variability during continuous incremental exercise test in obese subjects.

The present paper concerns a new description of changing in metabolism during incremental exercises test that permit an individually tailored program of exercises for obese subjects. We analyzed heart rate variability from RR interval time series (tachogram) with an alternative approach, the recurrence quantification analysis, that allows a description of a time series in terms of its dynamic structure and is able to identify the phase transitions. A transition in cardiac signal dynamics was detected and it perfectly reflects the aerobic threshold, as identified by gas exchange during an incremental exercise test, revealing the coupling from the respiratory system toward the heart. Moreover, our analysis shows that, in the recurrence plot of RR interval, it is possible to identify a specific pattern that allows to identify phase transitions between different dynamic regimes. The perfect match of the occurrence of the phase transitions with changes observed in the VO2 consumption, the gold standard approach to estimate thresholds, strongly supports the possibility of using our analysis of RR interval to detect metabolic threshold. In conclusion, we propose a novel nonlinear data analysis method that allows for an easy and personalized detection of thresholds both from professional and even from low-cost wearable devices, without the need of expensive gas analyzers.

Effects of an individualized home-based unsupervised aerobic training on body composition and physiological parameters in obese adults are independent of gender.

PURPOSE: Evaluation of the effects of an individualized home-based unsupervised aerobic training on body composition, physical and physiological parameters in female and male obese adults. METHODS: Two hundred and twenty obese adults (age 47.9 ± 12.4 years; BMI 38.0 ± 7.2 kg/m2) entered the 4-month training program. Body composition, physiological and functional capacities were assessed pre- and post-intervention. All subjects were requested to perform unsupervised aerobic training with the intensity based on heart rate, walking speed and OMNI-RPE score corresponding to the individual ventilatory threshold for at least 5 days/week. RESULTS: After 4-month study period, 40% of patients completed the protocol, 24% had high compliance (HC) (exercise ≥ 3 days/week), while 16% had low compliance (LC) to exercise prescription (exercise < than 3 days/week). In HC group, a significant improvement of body composition variables after training was performed. Moreover, oxygen uptake and metabolic equivalent at peak significantly increased after training. Six-minute walking test (6MWT) distance significantly increased while heart rate during 6MWT was significantly lower after training. No significant differences were found in LC group between pre- and post-intervention in all variables. Interestingly, gender does not influence the effects of training. CONCLUSIONS: Our results indicate that subjects, independent of gender, with high compliance to the aerobic training based on a new individualized method can achieve a significant reduction in weight loss and also an improvement in physical and physiological parameters. This innovative personalized prescription could be a valuable tool for exercise physiologist, endocrinologists, and nutritionists to approach and correct life style of obese subjects.

Effects of two physical education programmes on health- and skill-related physical fitness of Albanian children.

This study aims to evaluate the effectiveness of two school-based physical education (PE) programmes (exercise-based and games-based) compared with traditional PE, on health- and skill-related physical fitness components in children in Tirana, Albania. Participants were 378 first-grade (6.8 years) and 389 fourth-grade (9.8 years) children attending four randomly selected schools in Tirana. Twenty-four school classes within these schools were randomly selected (stratified by school and school grade) to participate as exercise group (EG), games group (GG) and control group (CG). Both EG and GG intervention programmes were taught by professional PE teachers using station/circuit teaching framework while CG referred to traditional PE school lessons by a general teacher. All programmes ran in parallel and lasted 5 months, having the same frequency (twice weekly) and duration (45 min). Heart rate (HR) monitoring showed that intensity during PE lessons was significantly higher in the intervention groups compared with control (P < 0.001). Both PE exercise- and games programmes significantly improved several health- and skill-related fitness indicators compared with traditional PE lessons (e.g. gross motor skill summary score: 9.4 (95% CI 7.9; 10.9) for exercise vs. control and 6.5 (95% CI 5.1; 8.1) for games vs. control, cardiorespiratory fitness: 2.0 ml O2 · min(-1) · kg(-1) (95% CI 1.5; 2.4) for exercise vs. control and 1.4 ml O2 · min(-1) · kg(-1) (95% CI 1.0; 1.8) for games vs. control). Furthermore, compared to games-based PE, exercise-based PE showed more positive changes in some gross motor coordination skills outcomes, coordination skills outcomes and cardiorespiratory fitness. The results from this study show that exercise- and games-based PE represents a useful strategy for improving health- and skill-related physical fitness in Albanian elementary school children. In addition, the study shows that exercise-based PE was more effective than games-based PE in improving gross motor function and cardiorespiratory fitness.

Acute physical activity and delayed attention in primary school students.

To examine the influence of different types of exertion on immediate and delayed attention in 116 primary school children divided in three groups of exertion [cognitive exertion - CE (school curricular lesson), physical exertion - PE (traditional physical education lesson), mixed cognitive and physical exertion - CPE (coordinative physical education lesson)]. CPE was the combination of physical load due to the practice of physical exercises and of cognitive load requested to perform movement-based problem solving tasks requiring accurate timing, temporal estimations, temporal production, and spatial adjustments. Children's attentional capacity was tested before (pre) and after (at 0 min and at 50 min post) a CE, a PE, or a CPE lesson, using the d2-test of attention, and analyzed using a 3 × 3 × 2 mixed analysis of covariance with exertion type and time as within factors, gender as between factor, and baseline data as covariate. Effect sizes were calculated as partial eta squared (ƞ(2)). Results showed that participants' attentional performance was significantly affected by exertion type (P < 0.0001), by time (P < 0.0001) and by exertion type × time interactions (P < 0.0001). The effect sizes ranged from medium (0.039) to large (0.437). Varying the type of exertion has different beneficial influences on the level of attention in school children.

Effects of Fitlight training on cognitive-motor performance in élite judo athletes.

Aims: The aims of this study were to verify if a 5-week cognitive-motor training (CMT) using FitlightsTM induced changes in young adult judo athletes compared to a non-intervention group. Specifically, it was verified if CMT influenced executive functions (EFs), physical fitness and brain-derived neurotrophic factor (BDNF) levels. Additionally, athletes' competitive results were compared between groups. Method: Twenty-seven athletes (14 males and 13 females; age = 19.5 ± 2.0 years) were assigned to the Fitlight (FG) and control (CG) groups which performed 5 weeks of CMT, respectively, including 25 min per day of Fitlight training or traditional judo practice. All participants performed cognitive (flanker task and forward/backward digit span) and fitness tests (counter movement jump, handgrip test, dynamic and isometric chin up). In addition, BDNF was collected by saliva sampling and competitive results after the intervention period were considered. Results: RM-ANOVA showed significant differences in FG for the accuracy of flanker (p = 0.028) and backward digit span (p < 0.001). Moreover, significant differences in FG were found for relative dynamic chin up (p = 0.027) and counter movement jump (p = 0.05). In addition, a significant difference in FG was found for competitive results after the intervention period (p < 0.01).No significant differences were found for BDNF and other cognitive and fitness measures (p > 0.05). Conclusion: A 5-week judo-specific CMT improved EFs and motor performance in élite judo athletes. It seems that CMT with Fitlight™ could be considered an additional support to coaches during the training period.

Exercise intensity and gender difference of 3 different salsa dancing conditions.

The aims of this study were to estimate the difference in exercise intensity (METs), energy cost (EE) and gender difference between a typical salsa lesson (TSL), rueda de casino lesson (RCL), and salsa dancing at a night club (SDN). Subjects performed 1 pre-testing session and 3 testing conditions. During the pre-testing session height, weight and V˙O2max were assessed. During the testing conditions all subjects performed 3 different kinds of salsa dance. Heart rate was assessed during each dance condition. The exercise intensity of the 3 salsa dancing conditions was moderate ranging from 3.9 to 5.5 METs. A significant difference between genders for HRpeak (P=0.01), max%HRR (P=0.006) and mean EE (P=0.02) were observed. Significant gender×condition interactions for HRpeak (P=0.03), mean %HRR (P=0.02), mean METs (P=0.02) and mean EE (P=0.02) were found. In addition, a significant main effect for each condition was found in all variables (P<0.01). Our results showed that the exercise intensities of all 3 salsa dancing conditions were moderate. Findings showed some significant differences in exercise intensity between males and females and within conditions. Salsa dancing could be useful in achieving a significant training effect in people who have a low level of fitness.

Does living setting influence training adaptations in young girls?

To assess whether rural or urban setting may influence young girls' fitness and coordinative abilities training adaptations following dance training. Forty-four dancers aged 11-12 years (21 urban, 23 rural) attended a 6-month dance training while continuing to practice their habitual physical activities (PA). Dancers' fitness and motor coordination abilities were assessed by pre- and post-intervention tests (anthropometric measures, 1-mile run/walk, sit and reach, standing long jump, hand grip and four field tests of kinaesthetic discrimination and response orientation). PA was assessed using a self-report recall measure. After the intervention period, rural dancers significantly improved in 1-mile run/walk, lower limb kinaesthetic discrimination and response orientation ability tests. Significant differences between two groups in upper limb response orientation ability test were found. Both groups showed a significant increase in body height and weight. Multiple regression analysis indicated that time in nonorganized PA predicted some fitness and coordinative changes (1-mile run/walk, lower limb response orientation and kinaesthetic discrimination ability tests) following the training period, although the percentage of variance it could explain was moderate. Our results showed that training adaptations of some fitness and coordinative performances could be influenced by setting characteristics that provided opportunities for different types of PA.

Linking coordinative and fitness training in physical education settings.

To assess whether an enrichment of the coordinative demands of physical education (PE) during the curricular time may more efficiently improve coordinative abilities than the traditional PE program. One hundred and fifty-two middle school students aged 11-12 years were randomly assigned either to an experimental (n=77) or to a traditional (n=75) PE program lasting 5 months. The experimental intervention was structured in different modules focused on co-ordination abilities. Pre- and post-intervention tests assessed students' fitness (1 mile run/walk, curl-up, flexed arm hang, trunk lift, sit and reach, 30 m run, standing long jump, basketball forward throw) and motor co-ordination abilities (four field tests of kinesthetic discrimination and response orientation ability). After the intervention period, both groups showed a significant increment in most fitness tests. However, only the experimental group showed a significant improvement or a significantly more pronounced improvement than the control group in coordinative performances. The results show that both experimental and traditional PE interventions lead to increase physical fitness levels, but only the experimental one also improves coordinative abilities. Thus, focusing on a multivariate PE approach linking co-ordination and fitness training seems to add quality to students' experiences without reducing their effectiveness in terms of physical fitness.

Assessing basketball ability in players with mental retardation.

BACKGROUND: Although athletes with mental retardation (MR) have achieved an important role, literature concerning the evaluation tests in basketball is still poor. OBJECTIVE: To assess basketball ability before and after a 4-month training performed before championship for athletes with MR and to correlate ability variations with MR levels. METHODS: 15 trained basketball players with MR (11 men and 4 women; age range 21-43 years; MR: 3 mild, 8 moderate, 8 severe and 1 profound). Athletes were tested before (pre) and after (post) 4 month training preceding the championship. The tests assessed 4 levels of ability, each one characterised by 4 fundamental areas of this game: ball handling, reception, passing and shooting. Each area was divided into 5 specific components. RESULTS: The team average score, based on the score of each athlete's 4 levels, improved by 6.6 points (41.6 (SD 11.9) vs 48.2 (14.7)). The comparison between pre and post scores in each level showed increases (p<0.01), especially in level II (14.4 (3.5) vs 16.5 (3.3)) and in level III (7.1 (5.7) vs 9.2 (6.6)). Within level II, ball handling (3.67 (1.2) vs 4.37 (0.5); p<0.05) and passing (3.20 (1.2) vs 3.97 (1.3); p<0.01) improved; in level III reception (3.21 (1.1) vs 3.73 (1.1); p = 0.01) and shooting (1.82 (1.1) vs 2.45 (1.3); p<0.05) increased. CONCLUSIONS: A 4 month training caused a general improvement, especially evident in levels II and III. Total score reached in level II was negatively correlated with MR level (r = -0.56; p<0.05), indicating that athletes with lower MR obtained higher scores.

Is explosive performance influenced by androgen concentrations in young male soccer players?

OBJECTIVE: There is growing interest in the implementation and assessment of strength and conditioning programmes among young children. The purpose of this study was to examine the association between given anthropometric characteristics, pubertal development, salivary androgen hormones and explosive leg power in young soccer players. METHODS: 51 (age range 10-14 years) soccer players were investigated. The relations between age, pubertal developmental stages, testicular volume, weight, height, body fat, fat free mass, salivary DHEAS concentrations, salivary testosterone concentrations and lower limb explosive power were evaluated. RESULTS: Standing long jump length was positively correlated (p<0.05) with age (11.7 (SD 1.2) years, r = 0.66), pubertal developmental stages (mode and range: 1 (1-4), r = 0.64), testicular volume (8.8 (5.2) ml, r = 0.58), height (1.50 (0.10) m, r = 0.34), weight (43.7 (9.1) kg, r = 0.34), fat free mass (35.4 (7.2) kg, r = 0.67), salivary DHEAS concentrations (4.4 (1.2) ng/ml, r = 0.38) and negatively correlated with body fat (18.6 (7.0) kg; r = -0.49, p<0.05). There was no significant correlation between salivary testosterone concentrations (0.3 (0.1) ng/ml, r = 0.12) and standing long jump. CONCLUSIONS: Results of the present investigation demonstrated that age, pubertal developmental stages, testicular volume, weight, height, fat free mass, and salivary DHEAS concentrations were associated with standing long jump performance. In addition, salivary testosterone concentrations were not related to explosive leg power. Results of the present investigation suggest that the teacher/coach should evaluate long jump performance relative to the subject's given biological characteristics, and not simply established standards based on chronological age.

Effect of tadalafil on anaerobic performance indices in healthy athletes.

OBJECTIVE: Given the therapeutic and non-therapeutic use of the tadalafil, (phosphodiesterase-5 inhibitor, PDE-5i), we examined its effects on anaerobic performance indices. METHODS: In total, 12 well-trained subjects reported to the laboratory on two occasions 1 week apart to perform a 30 s Wingate anaerobic power test (WAnT) on a bicycle ergometer. The day before the WAnT, the subjects were double-blinded to receive an oral dose of tadalafil (20 mg) or placebo. Blood lactate value at rest and 1, 3, 6 and 10 minutes of recovery phase, mean power, peak power, time to peak power and fatigue index were assessed for each WAnT. RESULTS: Blood lactate values at the 3-min recovery WAnT increased significantly in the tadalafil condition (mean (SD) 13.9 (1.7) v 12.8 (1.3) mmol/l; p<0.05) and time to peak power decreased significantly (6.3 (1.3) v 5.7 (1.5) s; p = 0.05). No differences were observed in any other parameters between the two conditions. CONCLUSION: The primary finding of this investigation was that the administration of a single dose of a long-term PDE-5i does not substantially influence anaerobic performance indices. However, results demonstrated both an increase in lactate values at the 3-min point of the recovery phase and a decrease in time to peak power.

Cortisol, dehydroepiandrosterone sulphate and dehydroepiandrosterone sulphate/cortisol ratio responses to physical stress in males are influenced by pubertal development.

To evaluate the influence of chronological age and pubertal development on the hypothalamus-pituitary-adrenal (HPA) axis response to stress, we studied the possible correlations between male pubertal characteristics and salivary cortisol (C), DHEAS and the DHEAS/C ratio before (pre-stress) and after acute exercise-stress in young male volunteers (no. 87; 13.3+/-2.1 yr). In our overall study population, the mean pre-stress salivary C and DHEAS concentrations, significantly increased after exercise-related stress, whereas the DHEAS/C ratio significantly decreased. Pre-stress salivary C was positively correlated with chronological age, and after-stress salivary C concentration variations were negatively correlated with pubertal stage, mean testis volume and pre-stress salivary DHEAS. Furthermore, salivary DHEAS concentrations and the DHEAS/C ratio, before and after exercise stress, were positively correlated with chronological age, pubertal stage, pre-stress salivary testosterone (T), testis volume and body mass index (BMI). In contrast with late pubertal stages (P4, P5), young individuals at early stages of puberty (P1 to P3) showed higher C increase and lower DHEAS/C ratio after exercise-related stress. In conclusion, since C is also a mediator of stress-related negative effects on health and the DHEAS/C ratio has been hypothesized as an index for the degree to which an individual is buffered against the negative effects of stress, these data might suggest potentially increased stress-related risks at early stages of male puberty.

The long-acting phosphodiesterase inhibitor tadalafil does not influence athletes' VO2max, aerobic, and anaerobic thresholds in normoxia.

Whereas experimental studies showed that in healthy trained subjects, the phosphodiesterase-5 inhibitor (PDE-5i) sildenafil improves exercise capacity in hypoxia and not in normoxia, no studies on the effects of the long half-life PDE-5i tadalafil exist. In order to evaluate whether tadalafil influences functional parameters and performance during a maximal exercise test in normoxia, we studied 14 healthy male athletes in a double-blind cross-over protocol. Each athlete performed two tests on a cycle ergometer, both after placebo or tadalafil (at therapeutic dose: 20 mg) administration. Oxygen consumption (VO2), blood lactate, respiratory exchange ratio, rate of perceived exertion, arterial blood pressure (BP), heart frequency (HR) and oxygen pulse (VO2/HR) were evaluated before exercise, at individual ventilatory and anaerobic thresholds (IVT and IAT), at VO2max and during recovery. Compared to placebo, a single tadalafil administration significantly reduced systolic BP before and after exercise (p < 0.05), decreased VO2/HR at IVT (13.3 +/- 1.8 vs. 14.5 +/- 2.1 mL . beat (-1); p = 0.03), but did not modify individual VO2max, IVT, or IAT. In healthy athletes, 20 mg of tadalafil does not substantially influence physical fitness-related parameters, exercise tolerance, and cardiopulmonary responses to maximal exercise in normoxia; it remains to be verified if higher doses/prolonged use influence health and/or sport performance in field conditions.

Exercise intensities during a ballet lesson in female adolescents with different technical ability.

To investigate the exercise intensity during a typical grade five ballet lesson, thirty-nine dancers (13 - 16 yrs) were divided into three different technical proficiency groups: low level (n = 13), intermediate level (n = 14), and high level (n = 12). A progressively incremented treadmill test was administered to determine VO(2max), individual ventilatory threshold (IVT), and the individual anaerobic threshold (IAT). Oxygen uptake (VO(2)), heart rate (HR) and blood lactate (La) were then evaluated during a grade five ballet lesson. Oxygen uptake at IVT, IAT and maximal oxygen uptake were greater (p < 0.05) in the high-level dancers indicating a higher level of fitness. HR and %VO(2max) obtained during the various exercises of the ballet lesson were similar among groups. During the ballet lesson, low technical level dancers had more V.O (2) and La values above (p < 0.05) the IAT than the other groups. Correlation analysis revealed that the number of exercises performed above IAT was positively related to anthropometric characteristics (BMI, %FM; r = 0.36, p < 0.05; r = 0.46, p < 0.01), negatively related to fitness parameters (VO(2IVT), VO(2IAT), VO(2max); r between - 0.43 and - 0.69; p < 0.001) and to technical level (r = - 0.70; p < 0.001). The subjects classified as having low technical abilities had lower fitness levels and performed more exercises above IAT than the more skilled dancers.

Salivary steroids at rest and after a training load in young male athletes: relationship with chronological age and pubertal development.

Puberty influences both the performance and the hormonal responses to exercise-related stress. We evaluated the distribution and the correlation between pubertal characteristics and the salivary cortisol (sC) and testosterone (sT) responses to acute physical exercise in young male athletes (13.4 +/- 2.1 yr, n = 110). The mean pre-exercise nmol . L (-1) sC and sT concentrations were 19.08 +/- 4.32 and 0.34 +/- 0.15 and increased to 21.27 +/- 5.51 and 0.41 +/- 0.16 after a 90-min training session (p < 0.01). The sC concentration at rest was positively correlated with chronological age (p < 0.01) and negatively correlated with fat % (p < 0.05), whereas significant negative correlations of DeltasC and DeltasC% after exercise with age, pubertal stage and mean testis volume (p < 0.05) were observed. The sT increase after exercise was correlated with chronological age, pubertal stage and pre-exercise sT levels (p < 0.01), whereas the DeltasT and DeltasT% of increase were negatively correlated with chronological age and resting sT levels (p < 0.05 and p < 0.01). In the present study, we observed the presence of high inter-individual variability of different biological parameters (anthropometry, pubertal stage, hormones, etc.) within athletes selected by chronological age in the same class and the presence of significant correlations between chronological age, puberty and the steroid hormone responses to physical exercise. Our data suggest the need for different criteria in exercise prescription and selection of young athletes and in the evaluation of stress reactivity at puberty.