Team sports practice and bone health: A systematic review and meta- analysis.

The primary aim of this study was to explore the effects of team sports practice on bone health indices in adults engaged in team sports. The secondary aim was to investigate the osteogenic effects of each type of team sport. This systematic literature search was conducted using common electronic databases from inception in June 2023, using key terms (and synonyms searched for by the MeSH database) that were combined using the operators "AND", "OR", "NOT": (``men'' OR ``man'' OR ``women'' OR ``woman'') AND (``bone mineral density'' OR ``BMD'' OR ``bone mineral content'' OR ``BMC'' OR ``peak bone mass'' OR ``mechanical loading'' OR ``osteoporosis'' OR ``bone geometry'' OR ``bone resistance'') AND (``team sport'' OR ``sport'' OR rugby OR basketball OR volleyball OR handball OR soccer OR football OR ``players''). After screening, 16 studies were included in the final analysis (5 continents, 2740 participants). The training duration lasted 1 to 13 years. Team sport training had a moderate impact on whole body bone mineral density (WB BMD) (1.07 SMD; 95 % [0.77, 1.37], p < 0.00) but a more significant impact on whole body bone mineral content (WB BMC) (1.3 SMD; 95 % [0.81, 1.79], p < 0.00). Subgroup analyses indicated that rugby training had a moderate but non-significant impact on WB BMD (1.19 SMD; 95 % [-0.13, 2.52], p = 0.08) but a greater impact on WB BMC (2.12 SMD; 95 % [0.84, 3.39], p < 0.00); basketball training had a moderate but significant impact on WB BMD (1 SMD; 95 % [0.35, 1.64], p < 0.00) and a trivial non-significant impact on WB BMC (0.18 SMD; 95 % [-1.09, 1.46], p = 0.78); volleyball training had a moderate but non-significant impact on WB BMD (0.63 SMD; 95 % [-0.22, 1.49], p = 0.15) and a significant impact on WB BMC (2.39 SMD; 95 % [1.45, 3.33], p < 0.00). Handball training produced a moderate significant impact on WB BMD (1.02 SMD; 95 % [0.33, 1.71], p < 0.00) and WB BMC (0.97 SMD; 95 % [0.47, 1.48], p < 0.00), and soccer training led to moderate but significant effects on WB BMD (1.16 SMD; 95 % [0.88, 1.44], p < 0.00) and a large effect on WB BMC (1.34 SMD; 95 % [0.92, 1.77], p < 0.00). Rugby training was associated with a higher WB BMC compared to basketball training (p = 0.03). Our systematic review and meta-analysis suggests that team sports, such as rugby, basketball, volleyball, handball and soccer have moderate to large effects on WB BMD and WB BMC. Specifically, our findings indicate that handball and soccer enhance WB BMD and WB BMC, whereas rugby only increases WB BMC. There is currently insufficient evidence indicating the superiority of any type of sport training that improves bone health in adults.

Effects of the Type of Exercise Training on Bone Health Parameters in Adolescent Girls: A Systematic Review.

Interventional studies offer strong evidence for exercise's osteogenic impact on bone particularly during growth. With rising osteoporosis rates in older women, enhancing bone strength early in life is crucial. Thus, investigating the osteogenic effects of different types of physical activities in young females is crucial. Despite varied findings, only two systematic reviews tried to explore this topic without examining how different types of exercise may affect bone health in adolescent girls. The first aim of this systematic review was to assess the impact of exercise training on bone health parameters in adolescent girls, and the second aim was to investigate whether the type of exercise training can modulate this effect. A systematic literature search was conducted using common electronic databases from inception - January 2023. Seven studies (355 participants) were eligible for inclusion in this systematic review. Two studies dealt with resistance training, 3 studies applied plyometric training, 1 study used team sports, and 1 study used dancing. Results indicate that plyometric training increases lumbar spine bone mass in adolescent girls. Well-designed randomized controlled trials with a proper training period (> 12 weeks) are needed to advocate a specific type of training which has the highest osteogenic effect.

The Effect of Whole-Body Electromyostimulation Program on Physical Performance and Selected Cardiometabolic Markers in Obese Young Females.

Background and Objectives: Whole-body electromyostimulation is under investigation as a potential aid for obesity-related health problems, supplementing a comprehensive, evidence-based obesity management strategy that includes lifestyle, diet, and exercise. The study investigated the impact of a whole-body electromyostimulation training program on physical performance and cardiometabolic markers in young obese females. Materials and Methods: Twenty-eight obese females, aged over 18 years with BMI over 30 and body fat over 28% and no underlying health conditions or medication, were divided into a whole-body electromyostimulation group (15 participants) and a control group (13 participants). The whole-body electromyostimulation program lasted 12 weeks, with two 20 min sessions weekly, using bipolar, rectangular current. Assessments pre and post intervention included body composition, blood pressure, lipid profile, C-reactive protein levels, maximal oxygen consumption, and jumping and sprint performance. Two-way ANOVA and t-tests were used for analysis. Results: Statistical analysis revealed significant (group × time) interactions for body composition, systolic blood pressure, maximal oxygen consumption, jumping and sprint performance, and plasma levels of lipids and C-reactive protein. Post hoc analyses for the whole-body electromyostimulation group indicated improvements in body composition indices (p < 0.01), systolic blood pressure (p = 0.003), maximal oxygen consumption (p = 0.010), and both jumping and 30 m sprint performance (p < 0.001 and p = 0.001, respectively) after the intervention. Furthermore, plasma levels of lipids (p < 0.01) and C-reactive protein (p = 0.002) showed significant improvements following the training program. In contrast, no significant changes were observed for these variables in the control group. Conclusions: A 12-week whole-body electromyostimulation program significantly improved body composition (skeletal muscle mass, body mass index, body fat, and waist circumference), physical performance (maximal oxygen consumption, jumping and sprint performance), and certain cardiometabolic (plasma level of lipids) and inflammatory markers (C-reactive protein) in obese young women. Further research is needed to explore the broader effects of whole-body electromyostimulation on physical and cardiometabolic health.

Ramadan Intermittent Fasting and Plasma Volume Variations in Individuals with Different Body Weights.

Background: There is increasing awareness of the physiological effects of Ramadan intermittent fasting (RIF) in obese subjects. However, there are no data on the effects of RIF on plasma volume changes (ΔPV) in individuals with different body weights. Background and Objectives: This study investigated the effects of RIF on ΔPV in normal-weight (NW) and overweight (OW) adult men, and adult men with obesity (OB) and severe obesity (SO). Materials and Methods: Thirty-two male subjects (32) were divided into four groups (n = 8 per group) according to their body mass index (BMI): normal weight (NW) (BMI < 25 kg/m2; age = 27.4 ± 3.8), overweight (OW) (BMI between 25 and 29.9 kg/m2; age = 26.8 ± 3.7), obese subjects (OB) (BMI between 30 and 34.9 kg/m2; age = 25.6 ± 2.9), and severely obesity (SO) (BMI between 35 and 40 kg/m2; age = 24.0 ± 4.1). Blood samples were collected for 24 h on 4 different occasions, at T0 before the start of the Ramadan month, at T1 15 days after the start of Ramadan, at T2 one day after the end of Ramadan, and at T3 on the 21st day after the end of Ramadan to determine ΔPV. All groups completed their fasting rituals for the 30 days of Ramadan. Results: A significant group × time effect occurred for body mass (p = 0.001; ES = 0.53), BMI (p = 0.001; ES = 0.53), and body fat percentage (p = 0.001; ES = 0.52). Post hoc tests indicated reductions in body mass in OB and SO at T1 (p = 0.03; ES = 0.21 and p = 0.002; ES = 0.12) and T2 (p = 0.03; ES = 0.31 and p = 0.02; ES = 0.23), reductions in BMI in OB and SO at T1 (p = 0.04; ES = 0.35 and p = 0.03; ES = 0.42) and T2 (p = 0.03; ES = 0.52 and p = 0.005; ES = 0.48), and reductions in body fat percentage only in OB AT T1 (p = 0.002; ES = 0.31) and T2 (p = 0.001; ES = 0.17). A significant group × time effect occurred for hematocrit (p = 0.02; ES = 0.34), hemoglobin (p = 0.01; ES = 0.35), and ΔPV (p = 0.02; ES = 0.18). Post hoc tests indicated increases in hematocrit in OB at T2 (p = 0.03; ES = 0.36) and hemoglobin in OB and SO at T1 (p = 0.03; ES = 0.35 and p = 0.002; ES = 0.32) and T2 (p = 0.003; ES = 0.21 and p = 0.002; ES = 0.33). There were also increases in ΔPV in OB at T1 and T2 (p = 0.002; ES = 0.25 and p = 0.003; ES = 0.22) and in SO only at T2 (p = 0.02; ES = 0.37). Contrast analysis indicated that NW was significantly lower than the grand mean of OW, Ob, and SO for all anthropometric and PVV variables (all p < 0.05). Conclusions: The effects of RIF on ΔPV and anthropometric characters was greater in obese individuals compared to normal-weight and overweight participants, suggesting that the improvements in body composition and ΔPV produced by RIF could positively influence obesity.

Acute effects of sodium citrate supplementation on competitive performance and lactate level of elite fitness challenge athletes: A crossover, placebo-controlled, double-blind study.

Purpose: The performance of sodium citrate has been investigated in high-intensity exercises, but fewer studies have addressed the role of citrate in weight-bearing exercises. Methods: Twenty fitness challenge athletes, aged 24-32 years, volunteered to participate in this crossover, placebo-controlled, double-blind study. Initially, ten athletes were given a placebo and asked to complete a fitness challenge (i.e., chin-ups, squat jumps, dips, walking lunges, sit-ups, and burpees-devil press). Another ten athletes were supplemented with sodium citrate 0.5 g/kg body mass supplements 3 h prior to performing the fitness challenges. The same procedures were completed two days later with the supplement and placebo dextrose groups switched in a cross-over design. Athletes and assessors were blinded for the experimental condition (placebo vs. verum). Lactate levels were measured 5 min after exercise. The athletes' performance on each item of the fitness challenge as well as their lactate levels, were compared. Differences between the means of the measured variables were contrasted using a dependent t-test. Results: Supplementing sodium citrate substantially improved athletes' performance in all six fitness challenge items (p < 0.05, 0.69

Effects of Kinesio Taping on Tuck Jump Performance in Competitive Male Athletes.

This study aimed to measure the acute effects of kinesio taping at different stretches on tuck jump performance in active individuals. Seventy-five males (23.01±2.24 years, 178.35±8.12 cm, 72.47±6.58 kg) were randomly distributed into three groups: (1) kinesio taping without stretch, (2) kinesio taping with approximately 50% stretch, and (3) kinesio taping with approximately 75% stretch. The tuck jump performance of all participants was determined at baseline, immediately after applying kinesio taping, and 24 and 72 hours later. The participants' tuck jump performance did not improve immediately after the kinesio taping application, 24 hours, and 72 hours after the application. No significant differences were found between the kinesio taping groups at any time point (p>0.05). This study demonstrated no effects of kinesio taping on neuromuscular performance.

The Effects of Exercise Training on Plasma Volume Variations: A Systematic Review.

The aim of this systematic review was to summarize the evidence on the acute and long-term effects of exercise training on PV, in both trained and untrained individuals and to examine associations between changes in %PVV and change in physical/physiological performance. Despite the status of participants and the exercise duration or intensity, all the acute studies reported a significant decrease of PV (effect size: 0.85

The Impact of Sport-discipline and Sex on Physical Fitness and Bone Markers in Athletes.

This study was performed to determine the impact of sex and sport-discipline on physical fitness and bone markers in young sub-elite track and field athletes. One hundred and forty-four track and field sub-elite athletes (78 males aged 17.8±1.6 years; 66 females aged 17.2±1.9 years) volunteered to participate in this study and were categorized according to their disciplines in endurance (EG: n=67) or power athletes (PG: n=77). A significant main effect of sex was observed for C-telopeptide type I collagen (CTx) (F=11.37; p<0.001; η2=0.10, moderate), for osteocalcin (OC) (F=8.58; p<0.004; η2=0.09, moderate) and for N-terminal propeptide of procollagen type I (PINP) (F=7.96; p<0.05; η2=0.07, moderate). The average CTx, OC and P1NP levels were significantly higher in males compared with females (0.05

Mental health, eating habits and physical activity levels of elite Iranian athletes during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic has changed life styles of millions of people worldwide. This study investigated changes in the health, physical activity levels and eating habits of elite athletes during the COVID-19 pandemic lockdown in Iran. METHODS: 383 (248 female and 135 male) elite athletes (168.82 ± 0.07 cm; 63.92 ± 7.42 kg; the body mass index (BMI): 22.3 ± 0.78 kg/m2) participated in this study. The International Physical Activity Questionnaire (IPAQ), Depression Anxiety Stress Scales (DASS-21) and the Impact of Event Scale-Revised (IES-R) study tools were used to measure levels of physical activity and mental health status, respectively. The Emotional Eater Questionnaire (EEQ) was used to assess food consumption related to emotion. Pearson and Spearman correlation analysis test were used in data analysis. RESULTS: Levels of depression and stress were mild and moderate, while levels of anxiety were severe and very severe in most elite athletes. There were levels of low emotional eating by elite athletes during the COVID-19 pandemic. Physical activity levels were negatively correlated with psychological mood measures (p≤0.05), while there were positive correlations between emotional eating behaviours and psychological mood measures (moderate correlation; p≤0.01) and light physical activity levels (weak correlation; p≤0.05). CONCLUSION: This study provides the first preliminary evidence showing that the COVID-19 lockdown conditions negatively influenced the eating habits and levels of physical activity and mental health in elite athletes. Regular high intensity physical activity as health strategy in elite athletes and the general population remains a strategy to improve overall health during the COVID-19 pandemic. Additionally, these findings suggest the need to devise strategies to improve the life styles of elite athletes during pandemics such as the Covid-19 pandemic.

CONTEXTE: La pandémie de COVID-19 a changé les modes de vie de millions de personnes dans le monde. Cette étude a examiné certains indicateurs de bonne santé, les niveaux d'activité physique et les habitudes alimentaires d'athlètes Elite iraniens pendant le confinement lié à la pandémie de COVID-19.Méthodes : 383 (248 femmes et 135 hommes) athlètes élites (168,82 ± 0,07 cm ; 63,92 ± 7,42 kg ; indice de masse corporelle (IMC) : 22,3 ± 0,78 kg/m2) ont participé à cette étude. Le questionnaire international sur l'activité physique (IPAQ), l'échelle DASS-21 (Depression Anxiety Stress Scales) et les scores de l'auto-questionnaire Impact of Event Scale-Revised (IES-R) ont été utilisés pour mesurer les niveaux respectifs d'activité physique et de l'état de santé mentale. L'Emotional Eater Questionnaire (EEQ) a été utilisé pour évaluer les altérations de la prise alimentaire liées à l'émotion. Le test d'analyse de corrélation de Pearson et Spearman a été utilisé pour l'analyse des données.Résultats : Les niveaux de dépression et de stress étaient légers et modérés, tandis que les niveaux d'anxiété étaient sévères à très sévères chez la plupart des athlètes élites. Il y avait des niveaux de faible alimentation d'origine émotionnelle chez ces athlètes pendant la pandémie de COVID-19. Les niveaux d'activité physique étaient corrélés négativement avec les mesures de l'humeur psychologique (p≤0,05), tandis qu'il y avait des corrélations positives entre les comportements alimentaires émotionnels et les mesures de l'humeur psychologique (corrélation modérée ; p≤0,01) et les niveaux d'activité physique légère (faible corrélation ; p≤0,05). CONCLUSION: Cette étude apporte une preuve préliminaire que les conditions de confinement liées au COVID-19 ont influencé négativement les habitudes alimentaires et les niveaux d'activité physique et de santé mentale chez des athlètes élites. L'activité physique régulière à haute intensité aussi bien chez les athlètes élites que pour la population générale reste une stratégie pour améliorer la santé globale pendant la pandémie de COVID-19. De plus, ces résultats suggèrent la nécessité de concevoir des stratégies pour améliorer les styles de vie des athlètes élites lors de pandémies, telles que celle de Covid-19.

Effects of Different Levels of Weightlifting Training on Bone Mineral Density in a Group of Adolescents.

The aim of the current study was to evaluate the effects of different levels of weightlifting training on bone mineral density (BMD) at different body sites (whole body (WB), lumbar spine (LS), femoral neck (FN), upper limbs (UL) and lower limbs (LL)) in a group of adolescents. Three groups of pubertal boys aged 13-15 years were recruited, including a control group (which included 13 untrained adolescents), a moderately trained group (which included 13 non-elite weightlifters, with four sessions of 2 hours per week) and a highly trained group (which included 13 elite weightlifters, with eight sessions of 2 hours per week). The three groups were paired for age and maturation index (using Tanner stages). Body composition, bone mineral content (BMC) and BMD were evaluated by dual-energy X ray absorptiometry (DXA). Physical performance variables (including weightlifting specific exercises, counter movement jump and squat jump) were measured using validated methods. Results showed that the values of BMD and physical performance variables were greater in the group of elite weightlifters compared to the group of non-elite weightlifters and the control group. In addition, the values of BMD and physical performance variables were higher in the group of the non-elite weightlifters compared to those of the control group. After adjusting for lean mass and squat jump, lumbar spine BMD, FN BMD, UL BMD and LL BMD remained significantly higher in the elite weightlifters' group compared to the two other groups. In conclusion, the current study suggests that elite adolescent weightlifters have greater bone health parameters compared to moderately-trained adolescent weightlifters and untrained adolescents.

High-intensity Interval Training Improves Lipocalin-2 and Omentin-1 Levels in Men with Obesity.

We investigated the effects of 12 weeks of high-intensity interval training (HIIT) on selected circulating adipokines and other cardiovascular diseases risks factors in men with obesity. Thirty men with obesity (age: 24.96±3.11 year, BMI: 30.92±1.04 kg/m2) were randomly assigned to HIIT and control groups. The HIIT group participated in a 12-week HIIT program (5×2 min interval bout at an intensity of 85-95% HRmax interspersed by 1 min passive recovery, three times per week), while the control group maintained their usual lifestyles. Blood lipids, insulin resistance, and select serum adipokines were assessed before and after 12 weeks of the intervention period. HIIT improved body composition and lipid profiles (p<0.05) and also decreased fasting insulin levels (p=0.001) and HOMA-IR (p=0.002) levels. Furthermore, HIIT increased levels of lipocalin-2 (p=0.002) while decreasing omentin-1 levels (p=0.001) in men with obesity. Changes in lcn2 and omentin-1 concentrations correlated with the changes in risk factors in the HIIT group (p<0.05). The results indicate that 12 weeks of supervised HIIT significantly improves both circulating concentrations of lcn2 and omentin-1, two recently described adipokines, and risk markers of cardiovascular diseases in men with obesity. Further research is necessary to understand the molecular mechanisms involved with these changes.

Inflammatory cytokines and metabolic responses to high-intensity intermittent training: effect of the exercise intensity.

To examine the effects of two high-intensity intermittent training (HIIT) programs of varying intensities (100% vs. 110% of maximal aerobic velocity [MAV]) on metabolic, hormonal and inflammatory markers in young men. Thirty-seven active male volunteers were randomly assigned into: HIIT experimental groups (100% MAV [EG100, n = 9] and 110% MAV [EG110, n = 9]) and a control groups (CG100, n = 9 and CG110, n = 9). Particpants performed high intesity intermittent exercise test (HIIE) at 100% or 110% MAV. Venous blood samples were obtained before, at the end of HIIE and at 15 min of recovery, and before and after 8 weeks of HIIT programs. After training, Glucose was lower (p < 0.01) in EG100 (d = 0.72) and EG110 (d = 1.20) at the end of HIIE, and at 15 min recovery only in EG110 (d = 0.95). After training, Insulin and Cortisol were lower than before training in EG100 and EG110 at the end of HIIE (p < 0.001). After HIIT, IL-6 deceased (p < 0.001) in EG100 (d = 1.43) and EG110 (d = 1.56) at rest, at the end of HIIE (d = 1.03; d = 1.75, respectively) and at 15 min of recovery (d = 0.88;d = 1.7, respectively). This decrease was more robust (p < 0.05) in EG110 compared to EG100. After HIIT, TNF-α deceased (p < 0.001) in EG100 (d = 1.43) and EG110 (d = 0.60) at rest, at the end of HIIE (0.71 < d < 0.98) and at 15 min of recovery (0.70 < d < 2.78). HIIT with 110% MAV is more effective in young males on the improvements of some metabolic (Glucose), hormonal (Cortisol) and inflammatory (IL-6) markers at rest, at the end of HIIE and 15 min of recovery than training at 100 % MAV.

Walking exercise and lower-body blood flow restriction: Effects on systemic inflammation, lipid profiles and hematological indices in overweight middle-aged males.

The objective of present study is to investigate the effects of walk training with and without blood flow restriction (BFR and no-BFR) on lipid profiles, inflammatory and haematological factors in over-weighed men. Participants were divided into BFR (n = 9) or no-BFR (n = 9) groups. Both groups were exposed to 8-week walk training on a treadmill: 3 sessions/week at a speed of 50 m/min, 5 sets × 2 min/session. There were differences in pre- to post-levels of (TG) and fibrinogen in the BFR group (p ≤ 0.05) that were accompanied by changes in red blood cells (RBC), haemoglobin (HGB) and haematocrit (HCT) levels (p ≤ 0.05). RBC levels were increased in the BFR group (p ≤ 0.05). The groups differed in their mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC). These findings suggest the efficiency of BFR walk training in individuals exposed to chronic diseases associated with overweight, such as metabolic syndrome.

Physical activity and adipokine levels in individuals with type 2 diabetes: A literature review and practical applications.

We review the effects of acute and long-term physical activity on adipokine levels in individuals with type 2 diabetes (T2D). Three electronic databases were searched. Studies made in animal models were excluded, while studies based on participants with and without T2D, and also studies with type 1 diabetes were included. Of the 2,450 citations, 63 trials, including randomised control trials, cross-sectional and longitudinal studies, met our inclusion criteria. Seventy and five percent of studies reported the effects of physical activity on tumor necrosis factor-alpha (TNFα), interleukin 6 (IL-6), adiponectin, visfatin, omentin-1, and leptin levels. There are no robust results due to variations in exercise modality, intensity, duration, and also differences in cohort characteristics in the literature. Only four studies described the effects of an acute session of physical activity on adipokine levels. Overall, physical activity improves diabetes status by regulating adipokine levels. However, long-term aerobic + resistance training combined with dietary modifications is likely to be a more effective strategy for improving adipokines profiles in patients with type 2 diabetes.

L-Arginine Improves Endurance to High-Intensity Interval Exercises in Overweight Men.

The effects of acute consumption of L-Arginine (L-Arg) in healthy young individuals are not clearly defined, and no studies on the effects of L-Arg in individuals with abnormal body mass index undertaking strenuous exercise exist. Thus, we examined whether supplementation with L-Arg diminishes cardiopulmonary exercise testing responses, such as ventilation (VE), VE/VCO2, oxygen uptake (VO2), and heart rate, in response to an acute session of high-intensity interval exercise (HIIE) in overweight men. A double-blind, randomized crossover design was used to study 30 overweight men (age, 26.5 ± 2.2 years; body weight, 88.2 ± 5.3 kilogram; body mass index, 28.0 ± 1.4 kg/m2). Participants first completed a ramped-treadmill exercise protocol to determine VO2max velocity (vVO2max), after which they participated in two sessions of HIIE. Participants were randomly assigned to receive either 6 g of L-Arg or placebo supplements. The HIIE treadmill running protocol consisted of 12 trials, including exercise at 100% of vVO2max for 1 min interspersed with recovery intervals of 40% of vVO2max for 2 min. Measurements of VO2 (ml·kg-1·min-1), VE (L/min), heart rate (beat per min), and VE/VCO2 were obtained. Supplementation with L-Arg significantly decreased all cardiorespiratory responses during HIIE (placebo+HIIE vs. L-Arg+HIIE for each measurement: VE [80.9 ± 4.3 L/min vs. 74.6 ± 3.5 L/min, p < .05, ES = 1.61], VE/VCO2 [26.4 ± 1.3 vs. 24.4 ± 1.0, p < .05, ES = 1.8], VO2 [26.4 ± 0.8 ml·kg-1·min-1 vs. 24.4 ± 0.9 ml·kg-1·min-1, p < .05, ES = 2.2], and heart rate [159.7 ± 6.3 beats/min vs. 155.0 ± 3.7 beats/min, p < .05, d = 0.89]). The authors conclude consuming L-Arg before HIIE can alleviate the excessive physiological strain resulting from HIIE and help to increase exercise tolerance in participants with a higher body mass index who may need to exercise on a regular basis for extended periods to improve their health.

Sprint and jump performances in highly trained young soccer players of different chronological age: Effects of linear VS. CHANGE-OF-DIRECTION sprint training.

OBJECTIVE: The aim of this study was to examine the effects of two different sprint-training regimes on sprint and jump performances according to age in elite young male soccer players over the course of one soccer season. METHODS: Players were randomly assigned to two training groups. Group 1 performed systematic change-of-direction sprints (CODST, U19 [n = 9], U17 [n = 9], U15 [n = 10]) while group 2 conducted systematic linear sprints (LST, U19 [n = 9], U17 [n = 9], U15 [n = 9]). Training volumes were similar between groups (40 sprints per week x 30 weeks = 1200 sprints per season). Pre and post training, all players performed tests for the assessment of linear and slalom sprint speed (5-m and 10-m), countermovement jump, and maximal aerobic speed performance. RESULTS: For all physical fitness measures, the baseline-adjusted means data (ANCOVA) across the age groups showed no significant differences between LST and CODST at post (0.061 < p < 0.995; 0.0017 < d < 1.01). The analyses of baseline-adjusted means for all physical fitness measures for U15, U17, and U19 (LST vs. CODST) revealed no significant differences between LST and CODST for U15 (0.213 < p < 0.917; 0.001 < d < 0.087), U17 (0.132 < p < 0.976; 0.001 < d < 0.310), and U19 (0.300 < p < 0.999; 0.001 < d < 0.049) at post. CONCLUSIONS: The results from this study showed that both, LST and CODST induced significant changes in the sprint, lower limbs power, and aerobic performances in young elite soccer players. Since no significant differences were observed between LST and CODST, the observed changes are most likely due to training and/or maturation. Therefore, more research is needed to elucidate whether CODST, LST or a combination of both is beneficial for youth soccer athletes' performance development.

Does green tea extract enhance the anti-inflammatory effects of exercise on fat loss?

AIMS: Green tea extract (GTE) can exert antiobesity and anti-inflammatory effects. Our study determined whether the benefits of GTE are summative with exercise-induced changes in anthropometric indices, and the levels of inflammatory cytokines, adiponectin and irisin in inactive overweight women. METHODS: Thirty overweight female participants were randomized to 3 groups: endurance training + placebo (ET + P); endurance training + GTE (ET + GTE); and Control (no exercise) + placebo (Control, n = 10). The exercise intervention consisted of an 8-week endurance-training programme of 3 sessions per week (aerobics, aerobic circuit training, and fast walking or jogging at a moderate intensity of 40-59% of the heart rate reserve). The dose of GTE used was 500 mg/day in the form of a green tea capsule. RESULTS: Body weight, body mass index, waist to hip ratio and body fat percentage were decreased in both ET + P and ET + GTE interventions (P < .001 for both interventions). The reduction of anthropometric values in the ET + GTE group was significantly higher than ET + P interventions (P < .001). Both exercise interventions also significantly (P < .001) increased adiponectin (ET + GTE = 5.28 mg/mL [95% confidence interval {CI}, 4.48 to 6.08] and ET + P = 3.34 mg/mL [95% CI, 2.76 to 3.92]) and decreased high-sensitivity C-reactive protein (hs-CRP; ET + GTE = -0.95 mg/L [95% CI, -1.15 to -0.75] and ET + P = -0.35 mg/L [95% CI, -0.46 to -0.24]). Changes in adiponectin and hs-CRP were greater (P < .05) in ET + GTE compared to ET + P. There were no significant differences in irisin, interleukin-6 or tumour necrosis factor-α between the 3 groups (P > .05). CONCLUSIONS: GTE improves exercise-induced body composition by further decreasing exercise-induced changes in weight, body mass index, waist to hip ratio and body fat percentage. The combination of GTE and exercise also produced greater changes in anti-inflammatory (increases in adiponectin) and metabolic (decreases in hs-CRP) markers than exercise alone.

Effects of green tea extract supplementation and endurance training on irisin, pro-inflammatory cytokines, and adiponectin concentrations in overweight middle-aged men.

PURPOSE: Green tea extract (GTE) supplementation has been proposed to possess anti-inflammatory properties. This study assessed the effects of GTE on endurance training (ET) induced changes on irisin, pro-inflammatory cytokines, adiponectin and anthropometric indices in overweight middle-aged males. METHODS: Participants were randomly assigned to three groups (n = 15): endurance training + placebo (ET + P), endurance training + green tea extract supplementation (ET + GTE), and no endurance training + placebo (P). The ET intervention consisted of an 8-week training program that included circuit training, fast walking or jogging performed three times/week at a moderate intensity (40-59% of the heart rate reserve). Participants received 500 mg/day GTE using a green tea capsule. Serum concentrations of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), irisin, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) were measured prior to and after the 8-week training intervention. RESULTS: Both exercise interventions decreased IL-6 and hs-CRP (p < 0.05), and increased adiponectin (p < 0.01) levels; changes in these variables were greater in the ET + GTE group compared to the ET + P and P groups (p < 0.01). Irisin concentrations increased only in the ET + GTE group and were different from the ET + P and P groups (p < 0.01). There were no changes in TNF-α concentrations in any of the groups. Both exercise interventions (ET + GTE and ET + P) decreased bodyweight, body mass index (BMI), body fat percentage (BFP), and visceral fat area (VFA) (p < 0.05), with greater changes in these variables occurring in the ET + GTE group compared to ET + P and P groups (p < 0.01). CONCLUSION: The combination of GTE supplementation and ET produces beneficial anti-inflammatory and metabolic effects, which were greater than those produced by ET alone.

Lower Cardiovascular Stress during Resistance Training Performed with Inter-Repetition Rests in Elderly Coronary Patients.

Background and Objectives: Hemodynamic stress during resistance training is often a reason why this training method is not used in cardiac patients. A lifting protocol that imposes rests between repetitions (IRRT) may provide less hemodynamic stress compared to traditional resistance training (TT). The aim of this study was to verify differences between set configurations on hemodynamic stress responses in resistance training. Materials and Methods: We compared hemodynamic (heart rate (HR), systolic blood pressure (SBP), and rate pressure product (RPP)) responses assessed with the auscultatory method in elderly (age = 75.3 ± 7.3 years) coronary male patients who were participating in a cardiac rehabilitation program allocated to either TT or IRRT with the same load (kg) and total number of repetitions (24) in the bilateral leg extension exercise. Results: IRRT resulted in significant lower values than TT for RPP at repetitions 8 (p = 0.024; G = 0.329; 95% CI: 0.061, 0.598) and 16 (p = 0.014; G = 0.483; 95% CI: 0.112, 0.854). Conclusions: IRRT appears to be a viable method of reducing the hemodynamic response (i.e., RPP) to resistance training and, thus, may contribute to the safety of cardiac rehabilitation programs. Further studies with more cardiac patients and other measurement techniques should be conducted to confirm these important findings.

Racial differences in hemoglobin and plasma volume variation: implications for muscle performance and recovery.

Objective: To examine the effect of race differences on sprint performance, Hemoglobin (Hb), Hematocrit (Ht) and plasma volume (PV) variation in response to repeated sprint exercise. Design: Thirty-six healthy, moderately trained men and women (20.8 ± 0.2 year-old) volunteered to participate in this study. They were allocated to one of the four groups according to their gender and race: Black men's group (BM, n = 9), White men's group (WM, n = 9), Black women's group (BW, n = 9) and White women's group (WW, n = 9). All participants performed the running-based anaerobic sprint test (RAST), which consists of six 35-m sprints with 10 s of recovery in-between. Six venous blood samples were collected to determine Hb, Ht and PV levels at rest, after warm-up, immediately post- and at 5, 15 and 30 min post-RAST. Blood lactate is also sampled during the 3rd minutes of recovery. Results: The best running time was significantly shorter (P = .002) in BW compared to WW. We have observed significantly higher Hb (P = .010) and Ht (P = .004) levels in BW compared to WW during the 5th minute of recovery. During RAST, the PV decreased significantly (P = .007) in WM only. Black groups had lower (P < .05) lactate levels compared to the white subjects. During recovery, PV increase was significantly (P = .003) higher in WW compared to BW during the 5th minute of recovery. Conclusion: This study demonstrated that sprint and repeated sprint performances were different between white and black women. Differences in anaerobic performance between the groups were associated with racial differences in lactate levels and blood count among women's group during recovery time. Hence, it is important to take into account this race-related difference in hematological parameters in responses to intense efforts.