The effect of weighted vest use during in-season, small-sided games training on young soccer players' performance.

The aim of the present study was to investigate the effect of weighted vest on-field small-sided games (SSG) soccer training, during the in-season period, on body composition and soccer-specific performances, in young, trained soccer players. A counterbalance study design was adopted, in which the fourteen well-trained players (age: 19.1 ± 0.5 yrs, body mass: 70.3 ± 5.3 kg, body height: 180.3 ± 3.0 cm, body fat: 9.2 ± 4.1%) performed both the Interventional (Vest) and Control (Con) training routines (6 weeks/season; 5 training sessions/week; 1 match/week), in different occasions (winter/spring period). Con group followed a regular weekly training plan. When the Con group performed their intense training sessions, Vest group performed only the on-field SSGs training wearing a vest (12.5% of athletes' body mass). All the evaluations were performed one week before and after each training period. Statistical analyses include repeated ANOVA and T-test (p < 0.05). Significant increases in sprinting, jumping, change of direction (COD), aerobic and anaerobic performances were observed only after Vest intervention (-4.7 ± 2.2% to 11.2 ± 4.2%; p < 0.05). Significant changes were observed only after Vest training, compared to Cont (p < 0.05). These results suggest that using a weighted vest, during the in-season, onfield SSG training two times/week induces greater increases in young soccer players' sprinting, jumping, COD, aerobic and anaerobic performances.

Effects of Four Weeks of In-Season Pre-Workout Supplementation on Performance, Body Composition, Muscle Damage, and Health-Related Markers in Basketball Players: A Randomized Controlled Study.

This randomized, double-blinded, experimental study investigated the effects of a four-week daily pre-workout supplementation (200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g ß-alanine, 6 g citrulline malate, and 5 g BCAA) vs. placebo (isocaloric maltodextrin) on anaerobic (jumping, sprinting, agility, and the running-based anaerobic sprint test: RAST) and aerobic (Yo-Yo intermittent recovery test level 1) performance, as well as on body composition and selective muscle damage/health-related blood markers in well-trained basketball players during the in-season period. Eighteen basketball players (age: 24.4 ± 6.3 years, height: 185.7 ± 8.0 cm, weight: 85.7 ± 12.8 kg, body fat: 16.5 ± 4.2%) were randomly assigned into two groups: pre-workout supplement (PWS, n = 10) or placebo (PL, n = 8). PWS consumption increased aerobic performance (PWS: 8 ± 6%; PL: -2 ± 6%; p = 0.004) compared to PL. A significant decrease was observed in peak (F = 7.0; p = 0.017), average (F = 10.7; p = 0.005), and minimum power (F = 5.1; p = 0.039) following 4 weeks of supplementation in both groups. No other significant changes were observed between groups (p > 0.05). In conclusion, the consumption of the current PWS over a four-week period appears to positively influence the aerobic performance of well-trained basketball players during the in-season period. However, it does not appear to mitigate the observed decline in anaerobic power, nor does it affect performance in jumping, sprinting, and agility, or alter body composition or selective muscle damage/health-related blood markers.

Type IIx muscle fibers are related to poor body composition, glycemic and lipidemic blood profiles in young females: the protective role of type I and IIa muscle fibers.

PURPOSE: The aim of the present study was to investigate the association between muscle fiber composition, body composition, resting glycemic-lipidemic blood profiles, in apparently healthy, young, active females. METHODS: Thirty-four young healthy female volunteers were allocated into two groups, depending on their Vastus Lateralis type IIx muscle fibers percent cross-sectional area (%CSA; H: high type IIx %CSA; L: low type IIx %CSA). Body composition was determined via dual-energy X-ray absorptiometry. Venous blood samples were collected for the determination of resting serum glucose, Insulin, Apo-A1, HOMA-IR, triglycerides (TG), total cholesterol (TC), High-density lipoprotein (HDL-C), and Low-density lipoprotein (LDL-C) concentrations. Nutritional intake was also evaluated. RESULTS: Individuals of the H group have significantly higher body mass, body fat percentage-mass, and resting blood indices of glycemic and lipidemic profiles, compared to those of L group (p < 0.001). Increased type IIx and low type I, IIa muscle fibers %CSAs were linked with poorer body composition, glycemic and lipidemic blood profiles (r: - 0.722 to 0.740, p < 0.001). Linear regression analyses revealed that the impact of muscle fibers %CSA (B coefficients ranged between - 0.700 and 0.835) on the above parameters, was at least, of the same or even of greater magnitude as that of body composition and daily nutritional intake (B: - 0.700 to 0.666). CONCLUSION: Increased type IIx and low Type I, IIa %CSAs are associated with poorer body composition and glycemic-lipidemic profiles in young healthy females. The contribution of the muscle fiber %CSA on health status seems to be comparable to that of nutrition and body composition.

Redox Profile of Skeletal Muscles: Implications for Research Design and Interpretation.

Mammalian skeletal muscles contain varying proportions of Type I and II fibers, which feature different structural, metabolic and functional properties. According to these properties, skeletal muscles are labeled as 'red' or 'white', 'oxidative' or 'glycolytic', 'slow-twitch' or 'fast-twitch', respectively. Redox processes (i.e., redox signaling and oxidative stress) are increasingly recognized as a fundamental part of skeletal muscle metabolism at rest, during and after exercise. The aim of the present review was to investigate the potential redox differences between slow- (composed mainly of Type I fibers) and fast-twitch (composed mainly of Type IIa and IIb fibers) muscles at rest and after a training protocol. Slow-twitch muscles were almost exclusively represented in the literature by the soleus muscle, whereas a wide variety of fast-twitch muscles were used. Based on our analysis, we argue that slow-twitch muscles exhibit higher antioxidant enzyme activity compared to fast-twitch muscles in both pre- and post-exercise training. This is also the case between heads or regions of fast-twitch muscles that belong to different subcategories, namely Type IIa (oxidative) versus Type IIb (glycolytic), in favor of the former. No safe conclusion could be drawn regarding the mRNA levels of antioxidant enzymes either pre- or post-training. Moreover, slow-twitch skeletal muscles presented higher glutathione and thiol content as well as higher lipid peroxidation levels compared to fast-twitch. Finally, mitochondrial hydrogen peroxide production was higher in fast-twitch muscles compared to slow-twitch muscles at rest. This redox heterogeneity between different muscle types may have ramifications in the analysis of muscle function and health and should be taken into account when designing exercise studies using specific muscle groups (e.g., on an isokinetic dynamometer) or isolated muscle fibers (e.g., electrical stimulation) and may deliver a plausible explanation for the conflicting results about the ergogenic potential of antioxidant supplements.

The Effect of Acute Pre-Workout Supplement Ingestion on Basketball-Specific Performance of Well-Trained Athletes.

A pre-workout supplement's (PWS; 200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g ß-alanine, 6 g citrulline malate and 5 g branched chained amino acid (BCAA) per dose) acute effects on the alactic (jumping, sprinting, agility), lactic (Running-Based Anaerobic Sprint Test, RAST) and aerobic performance (Yo-Yo Intermittent Recovery Test Level 1, Yo-Yo IRL1 VO2max) of well-trained basketball players was investigated in this double-blind placebo-controlled study. Thirty players (age 18-31 years, height 166-195 cm, weight 70.2-116.7 kg, body fat 10.6-26.4%) were allocated to pre-workout (PWS, n = 15) or placebo (PL, n = 15) groups. Half of the participants in each group performed the evaluations without PWS or PL, while the rest consumed PWS or PL 30 min before the assessments (1st trial) and vice versa (2nd trial). Significant improvements in counter-movement jump (CMJ) (PWS: 4.3 ± 2.1%; PL: 1.2 ± 1.0%), agility (PWS: -2.9 ± 1.8%; PL: 1.8 ± 1.7%), RAST average (PWS: 18.3 ± 9.1%; PL: -2.2 ± 2.0%), minimum power (PWS: 13.7 ± 8.9%; PL: -7.5 ± 5.9%), and fatigue index (PWS: -25.0 ± 0.9%; PL: -4.6 ± 0.6%) were observed in the PWS group vs. the PL group (p < 0.05). No differences were found regarding sprinting, aerobic performance, and blood lactate concentrations. Thus, although players' alactic and lactic anaerobic performance could be improved, peak power, sprinting and aerobic performance are not.

Skeletal muscle fiber composition may modify the effect of nutrition on body composition in young females.

BACKGROUND AND AIM: The aim of this study was to investigate the hypothesis that healthy, normal-weight females with greater proportions and sizes of the oxidative muscle fibers would also be characterized by a healthier body composition compared with individuals with increased glycolytic fibers, even if both follow similar nutritional plans. METHODS AND RESULTS: Vastus lateralis muscle fiber-type composition, body composition through dual-energy X-ray absorptiometry, and dietary intakes through questionnaire were evaluated in twenty-two young, healthy, non-obese females (age: 21.3±1.8yrs, body mass: 67.5±6.2 kg, body height: 1.66±0.05m, body mass index (BMI): 24.2±2.6  kg m-2). The participants were allocated into two groups according to their type I muscle fibers percentage [high (HI) and low (LI)]. The participants of the LI group were characterized by significantly higher body mass, fat mass, BMI, and cross-sectional and percentage cross-sectional area (%CSA) of type IIx muscle fibers compared with participants of the HI group (p < 0.021). In contrast, the HI group was characterized by higher cross-sectional and %CSA of type I muscle fibers compared with the LI group (p < 0.038). Significant correlations were observed between body fat mass, lean body mass, total energy intake, fat energy intake, and %CSAs of type I and IIx muscle fibers (r: -0.505 to 0.685; p < 0.05). CONCLUSION: In conclusion, this study suggests that muscle fiber composition is an important factor that at least partly could explain the observed differential inter-individual responses of the body composition to nutrition in female individuals. Increased %CSAs of type I muscle fibers seem to act as a protective mechanism against obesity and favor a healthier body composition, neutralizing the negative effect of increased caloric fats intake on body composition, probably because of their greater oxidative metabolic properties and fat utilization capacities. In contrast, female individuals with low type I and high type IIx %CSAs of type I seem to be more metabolically inflexible and dietinduced obesity prone, even if they consume fewer total daily calories and fats.

Nutrition, body composition and physical activity have differential impact on the determination of lipidemic blood profiles between young females with different blood cholesterol concentrations.

INTRODUCTION: This cross-sectional study explored whether nutrition, body composition, and physical activity energy expenditure (PAΕΝ) have a differential impact on lipidemic blood profiles among young females with different blood cholesterol concentrations. METHODS: One hundred thirty-five young female students (N = 135) were allocated into three groups according to their blood cholesterol concentrations (Chol): (A) Normal [NL; Chol: < 200 mg·dL-1; n = 56 Age: 21.4 ± 2.6 yrs, Body Mass Index (BMI): 22.1 ± 2.0 kg·m-2], (B) Borderline (BL; Chol: ≥200 mg·dL-1 and <240 mg·dL-1; n = 44 Age: 21.6 ± 2.5 yrs, BMI: 24.2 ± 3.1 kg·m-2) and (C) High level (HL; Chol: ≥240 mg·dL-1; n = 35 Age: 22.5 ± 2.4 yrs, BMI: 28.9 ± 2.1 kg·m-2). Body composition [bioelectrical impedance analysis including lean body mass (LBM) and body fat mass], nutritional intake (recall questionnaire), daily physical activity energy expenditure through activity trackers and resting blood lipids concentrations were evaluated. RESULTS: Multiple linear regression analyses revealed that in the NL group, lean mass, daily PAΕΝ and daily energy balance were the determinant parameters of blood lipidemic profiles (B: -0.815 to 0.700). In the BL group, nutrition, body composition and daily physical activity energy expenditure exhibited similar impacts (B: -0.440 to 0.478). In the HL group, nutritional intake and body fat mass determined blood lipidemic profile (B: -0.740 to 0.725). CONCLUSION: Nutrition, body composition and daily PAΕΝ impact on blood lipids concentration is not universal among young females. In NL females, PAEN, energy expenditure and LBM are the strongest determinants of blood lipids, while in HL females, nutritional intake and body fat mass are. As PAΕΝ increases, the importance of nutrition and body fat decreases, and vice versa.

Different eccentric-based power training volumes improve glycemic, lipidemic profile and body composition of females in a dose-dependent manner: Associations with muscle fibres composition adaptations.

The present study aimed to investigate the effect of different volumes of fast eccentric-based training on body composition and lipidemic-glycemic profiles in females, as well as to explore the relationship between the change in glycemic-lipidemic profiles and the change in muscle fibre composition. Twenty-nine young females were assigned into three groups and performed 10 weeks (2 training sessions per week) of either 3 (LV), 6 (MV) or 9 (HV) sets/session of four fast velocity eccentric-only half-squats against 70% of concentric 1RM, followed by 3 maximum countermovement jumps (CMJ) after each set. Body composition, vastus lateralis fibre-type composition, and resting blood lipidemic and glycemic indices were evaluated 1 week before and after the training intervention. Significant changes in body composition, fasting glucose, HOMA-IR and blood lipids were found after training with MV and HV (p < 0.05; η2: 0.135-0.390). Significant correlations were found between muscle fibres' percentage cross-sectional areas (%CSA) and resting glycemic-lipid values (r:-0.543to 0.730, p < 0.05). Training-induced changes of glycemic-lipid profiles were highly correlated to those of type IIa and IIx %CSAs (r: -0.895 to 0.898, p < 0.05). Partial Correlations revealed a significant impact of the imposed training volumes on these correlations. These results suggest that six but mostly nine sets per training session of the imposed training stimuli are needed for beneficial changes in resting glycemic-lipidemic profiles, changes which are related to the training-induced changes in muscle fibre composition. However, these relationships are dictated by the imposed training volumes.Highlights Power training induces beneficial changes in body composition, glycemic and lipidemic profiles.Greater training volumes are needed for the healthier changes in glycemic-lipidemic profiles.Higher Type I, IIA and lower IIX percentage cross-sectional areas are linked with healthier body composition and glycemic-lipidemic profiles.Individuals experiencing the greatest increase in Type IIa and decrease in Type IIX muscle fibres cross-sectional areas after power training are those with the greatest beneficial changes in body composition, glycemic and lipidemic profiles.

The effect of gender, age and sports specialisation on isometric trunk strength in Greek high level young athletes.

Aim of the study was to compare the isometric strength of flexors and extensors trunk muscles between male and female elite adolescent athletes of different age and training experience. Absolute and relative trunk muscle isometric peak extension (PTE) and flexion (PTF) torque, as well as flexion/extension (F/E) ratio were evaluated in 388 elite adolescent athletes 188 males (Age: 15.4±1.8 years, Body height: 175.5±11.2 cm, Body mass: 68.8±14.5 kg, BMI: 22.1±0.3 kg/m2) and 207 females (Age: 15.1±1.6 years, Body height: 166.8±7.8 cm, Body mass: 60.8±8.4 kg and BMI: 21.8±0.4 kg/m2). Participants were assigned into seven different groups according to their sport specialisation (oars-paddle, swimming, contact-combat, team, racket, winter and mixed other sports). Significant effect of age (η2: 0.077-0.112, p < 0.05), gender (η2: 0.020-0.077; p < 0.05) and sport category factors (η2: 0.057-0.154. p < 0.005) for absolute/relative PTE, PTF and F/E ratio was found. The highest values were observed in contact-combat and the lowest in mixed other sports groups. F/E ratio significantly differs between the age groups, especially in female athletes. The present data suggest that TMSs and F/E ratio are highly affected by age, gender and sports specialisation in high level trained adolescents.

Changes in Body Weight, Body Composition, Phase Angle, and Resting Metabolic Rate in Male Patients with Stage IV Non-Small-Cell Lung Cancer Undergoing Therapy.

Background and Objectives: Cancer treatments can adversely influence body weight status, body composition, phase angle (PhA), and resting metabolic rate (RMR), which could possibly affect disease course. Τhe aim was to assess differences in body composition, PhA, RMR, and related parameters in non-small-cell lung cancer (NSCLC) patients after treatment. Methods: The sample consisted of 82 NSCLC (stage IV) male patients (chemotherapy (C) 15.7%; immunotherapy (I) 13.3%; C + I 25.3%; (C) + radiotherapy (R) 22.9 %; and other 15.5%). Body weight and body composition, PhA, RMR, oxygen consumption (VO2), ventilation rate, and diet were assessed at baseline and at 3 months after initiation of therapy. Results: Reductions in PhA, RMR, VO2, ventilation rate, and intracellular water were observed at follow up. Weight loss was evident for 45% of patients who also had a reduction in lean body mass. In the group under C, lean mass was reduced at follow up (55.3 ± 11.53 vs. 52.4 ± 12.6, p = 0.04) without significant weight changes. In subjects with a low adherence to the Mediterranean diet (MedDietScore < 30), RMR (1940 ± 485 vs. 1730 ± 338 Kcal, p = 0.001), VO2 (277.1 ± 70.2 vs. 247 ± 49.1 mL/min, p = 0.001), and ventilation rate (10.1 ± 2.28 vs. 9. ± 2 2.2 L/min, p = 0.03) were significantly reduced. The changes in body weight were positively related to % of change in fat mass (rho = 0.322, p = 0.003) and absolute lean mass change (rho = 0.534, p < 0.001) and negatively associated with % of change in total body water (rho = −0.314, p = 0.004) (Spearman correlation coefficients). Conclusions: In conclusion, cancer therapy related to reductions in PhA and RMR, while lean mass reduction may be related to the type of treatment. Our results emphasize the importance of a more holistic nutritional and body composition assessment beyond body weight, to better address patients' needs in clinical practice.

Dietary Habits Are Related to Phase Angle in Male Patients with Non-Small-Cell Lung Cancer.

Introduction: Lung cancer constitutes the most common cause of cancer death. Phase angle (PhA) has been related to lung cancer prognosis, which implies that the identification of dietary or other factors that could predict or modify PhA may have beneficial effects. Νutritional interventions have been linked with positive changes in PhA in certain types of cancer. Aim: The present study aimed to investigate the relationships between dietary habits/nutrition and PhA in NSCLC patients. Methods: The sample consisted of 82 male patients with non-small-cell lung cancer (NSCLC; stage IV) from the 'Theageneio' Cancer Hospital (Thessaloniki, Greece). Several parameters were assessed, such as body mass index (BMI), lean mass, PhA, Mediterranean diet score (MedDietScore), dietary patterns, smoking, resting metabolic rate, resting oxygen consumption (VO2), ventilation rate, and physical activity. Results: According to our results, a dietary pattern rich in potatoes and animal proteins (meat and poultry) was a significant determinant of PhA (B ± SE, p: 0.165 ± 0.08, p = 0.05) in multiple linear regression models after adjusting for age, smoking, lean tissue, and MedDietScore. Conclusion: In conclusion, dietary patterns may affect PhA, suggesting the crucial role of protein in cancer management and the prevention of sarcopenia.

Body Composition, Fasting Blood Glucose and Lipidemic Indices Are Not Primarily Determined by the Nutritional Intake of Middle-Aged Endurance Trained Men-Another "Athletes' Paradox"?

Systematic, regular high-volume endurance training induces significant metabolic adaptations in glucose and lipids metabolism, which seems to affect the negative impact of unhealthy nutrition, at least in animal models. The present study aimed to investigate the main determinants of body composition, blood glucose and lipids concentrations between middle-aged sedentary individuals (Sed) and well-trained endurance athletes (Run), both following an unhealthy high-fat diet. In thirty-five Sed (Age: 54.0 ± 6.6 yrs, Body Mass: 77.1 ± 10.5 kg, BMI: 31.3 ± 6.0 kg·m-2) and thirty-six Run (Age: 51.6 ± 5.2 yrs, Body Mass: 85.8 ± 3.4 kg, BMI: 23.2 ± 1.8 kg·m-2), body composition, nutritional intake, energy expenditure, resting metabolic rate (RMR), respiratory exchange ratio (RER), and blood glucose and lipids concentrations were evaluated. Multiple linear regression analyses revealed that body composition, blood glucose and lipids' concentrations in the Run group were primarily determined by the energy expenditure (B: -0.879 to -1.254), while in the Sed group, by their energy intake (B:-0.754 to 0.724). In conclusion, it seems that in well-trained endurance middle-aged athletes, body composition, blood glucose, and lipids concentrations seem to be determined by their training-induced daily energy expenditure and not by their nutritional intake per se. At the same time, nutrition is the primary determinant in aged-matched sedentary individuals, even if they both follow high-fat diets.

Validity and Reliability of New Equations for the Prediction of Maximal Oxygen Uptake in Male and Female Elite Adolescent Rowers.

The aim of this study was to develop accurate, reliable, and reproductive equations for the prediction of maximum oxygen uptake ( V ˙ O2max) in male and female high-level adolescent rowers. This study included two parts. In the first part, V̇O2max was evaluated in 106 male and 83 female high-level adolescent rowers during an incremental step test (IRT) on a rowing ergometer, and stepwise multiple regression analyses were used for the development of new equations. In the second part, these equations were tested in 26 new high-level adolescent rowers of the same age and anthropometrical characteristics (boys: 15.27 ± 2.70 yrs and 15.34 ± 2.80 yrs; 72.37 ± 10.96 kg and 70.96 ± 10.65 kg; girls: 15.00 ± 2.11 yrs and 15.94 ± 2.71 yrs; 62.50 ± 7.14 kg and 63.41 ± 6.72 kg for parts 1 and 2, respectively; p > 0.05). V̇O2max was predicted from the combination of lean body mass (LBM) and the distance covered during the last 4 min stage of the IRT (boys: r2 = 0.715, F = 68.74, p = 0.001; girls: r2 = 0.769, F = 57.81, p = 0.001). In the second part, no significant differences were identified when the new equations were tested against measured V̇O2max (boys: 3971.15 ± 713.38 mL·min-1 vs. 3915.83 ± 704.43 mL·min-1; girls: 3272.75 ± 551.46 mL·min-1 vs. 3308.94 ± 557.59 mL·min-1 for measured and predicted values, respectively; p > 0.05). In conclusion, V̇O2max of high-level adolescent rowers can be predicted with high accuracy, reliability, and repeatability using simple and easily evaluated anthropometric and performance variables.

The emerging role of skeletal muscle as a modulator of lipid profile the role of exercise and nutrition.

The present article aims to discuss the hypothesis that skeletal muscle per se but mostly its muscle fiber composition could be significant determinants of lipid metabolism and that certain exercise modalities may improve metabolic dyslipidemia by favorably affecting skeletal muscle mass, fiber composition and functionality. It discusses the mediating role of nutrition, highlights the lack of knowledge on mechanistic aspects of this relationship and proposes possible experimental directions in this field.

Effects of Complex Vs. Compound Training on Competitive Throwing Performance.

ABSTRACT: Thomas, K, Spyridon, M, Nikolaos, Z, Angeliki-Nikolleta, S, Giorgos, K, Giorgos, G, and Gerasimos, T. Effects of complex vs. compound training on competitive throwing performance. J Strength Cond Res 36(7): 1866-1874, 2022-The purpose of this study was to investigate the effects of complex (CPX; strength and power exercises in pairs) vs. compound (CPD; strength and power exercises in different days) training on competitive track and field throwing performance. Ten well-trained throwers (7 male throwers and 3 female throwers) followed a 34-week periodized training program including 2 preparation periods. During the winter 4-week, precompetition phase, athletes were randomly assigned to CPX or CPD groups, while the opposite assignment was performed during the spring precompetition phase (counterbalanced design). Before and after each training period competitive track and field throwing performance, shot put throws, snatch, squat and bench press 1 repetition maximum (1RM), vertical jumps, rate of force development (RFD), and body composition were evaluated. Competitive track and field throwing performance increased significantly by 5.4 ± 2.9% and 1.9 ± 1.7%, after CPX and CPD, respectively, with a significant difference between groups (p < 0.001). Shot put throws and 1RM strength in bench press increased similarly after both programs (p < 0.05), but vertical jumps increased only after CPX training. CPX induced greater increases in 1RM strength in snatch and squat, RFD, and lean body mass compared with CPD (p < 0.005). The linear combination of training-induced changes in RFD 150ms, 1RM in squat, snatch, and total lean mass explained the 80% of the percentage increase in competitive track and field throwing performance (p = 0.007). These results suggest that 4 weeks of CPX training during the precompetition period induce greater increases in competitive track and field throwing performance, 1RM strength, power, and RFD compared with CPD training.

Exploring the predictors and prognostic significance of exercise-induced cardiac troponin release in master athletes following a 28 km mountain race. The Vamvakou research project.

BACKGROUND/OBJECTIVE: Aetiology and significance of exercise-induced troponin release remains a contentious issue. We investigated the effect of a 28 km mountain run on cardiac troponin I (cTnI), in relation to training, performance, nutritional, biochemical and echocardiography variables, in a group of 25 recreational male master athletes. MATERIAL AND METHODS: A comprehensive list of variables related with nutrition, training, performance and echocardiography, was collected pre- and post-race. Twenty-four months later, outcomes regarding cardiovascular events were obtained. RESULTS: Serum cTnI values were increased after the race, with mean values rising from 7.2 ± 2.2 (before) to 80.0 ± 33.2 ng/L (post race), (p < 0.001) and 23/25(92%) exceeding Upper Reference limit (50 ng/L). Echocardiography did not reveal significant alterations, or correlations with cTnI values. The percentage difference in hs-cTnI concentrations pre- and post-race correlated positively with age, race-induced changes of selected muscle damage indices, resistance training volume and negatively with endurance capacity and training volume (r: -0.727 to 0.725, p < 0.05). All athletes reported no cardiovascular event during the 24-month period post-race. CONCLUSION: cTnI elevation induced by a 28 km mountain running race was not correlated with echocardiographic, nutritional parameters and was less pronounced in athletes with larger endurance training history, in contrast with resistance training and age.

Comparison of short-term hypocaloric high-protein diets with a hypocaloric Mediterranean diet: Effect on body composition and health-related blood markers in overweight and sedentary young participants.

OBJECTIVES: The aim of the present study was to compare the short-term effects of a hypocaloric Mediterranean diet and two high protein diets, with and without whey protein supplementation, on body composition, lipidemic profile, and inflammation and muscle-damage blood indices in overweight, sedentary, young participants. METHODS: Thirty-three young, overweight, male and female participants (mean ± SD age: 22.8 ± 4.8 y; body mass: 85.5 ± 10.2 kg; body fat percentage: 34.3% ± 8.1%) were randomly allocated to three different hypocaloric (-700 kcal/d) diets: a Mediterranean diet (MD; n = 10), a high-protein diet (HP; n = 10) diet, and a high-protein diet with whey supplementation (n = 10). The intervention lasted 6 wk. Body composition and biochemical indices were evaluated 1 wk before and after the nutritional interventions. RESULTS: Body and fat mass were decreased in the MD and HP groups (-3.5% ± 1.1% and -5.9% ± 4.2% for body and fat mass respectively in MD, and -1.7% ± 1.2% and -2.0% ± 1.8% for body and fat mass respectively in HP;P < 0.05), with no significant decline of fat-free mass observed in the MD group. The MD group's diet beneficially altered the lipid profile (P < 0.05), but the HP and HPW groups' diets did not induce significant changes. Subclinical inflammation and muscle-damage indices significantly increased in the HP and HPW groups (7.4% ± 3.5% and 66.6% ± 40.1% for neutrophils and CRP respectively in HP, and 14.3% ± 6.4% and 266.6% ± 55.1% for neutrophils and CRP respectively in HPW; P < 0.05) but decreased in the MD group (1.8% ± 1.2% and -33.3% ± 10.1% for neutrophils and CRP respectivelyc; P < 0.05). Energy intake of carbohydrates and proteins were significantly related to the changes in body composition and biochemical blood markers (r = -0.389 and -0.889; P < 0.05). CONCLUSIONS: Among the three hypocaloric diets, only the Mediterranean diet induced positive changes in body composition and metabolic profile in overweight, sedentary individuals.

Weak Association Between Vastus Lateralis Muscle Fiber Composition and Fascicle Length in Young Untrained Females.

The aim of the study was to investigate the relationships between vastus lateralis muscle fiber length and fiber type composition in individuals with minimal exposure to systematic resistance/power training. In sixty female physical education students (age: 21.03 ± 2.1 years, body weight: 59.8 ± 9.7 kg, body height: 166.2 ± 6.5 cm), with no experience in systematic training, lean body mass, VL muscle architecture and fiber composition type, countermovement jumping (CMJ) performance, and isometric leg press rate of force development were evaluated. Data were analyzed for all participants, as well as two equally numbered groups assigned according to their maximum countermovement jumping power (High-Power or Low-Power group). Significant but low correlations were found between type II muscle fiber percentage and fascicle length (N = 60, p < 0.05). Significant correlations were found between type IIa and IIx muscle fiber percentage cross-sectional area (%CSA) and fascicle length (N = 60; r = 0.321, and r = 0.378; respectively, p < 0.05). These correlations were higher for the High-Power group (r = 0.499, and r = 0.522; respectively, p < 0.05), and lower, and nonsignificant, for the Low-Power group. The best predictor of strength/power performance was the lean body mass of the lower extremities (r = 0.389-0.645, p < 0.05). These results suggest that in females with minimal exposure to systematic training, fascicle length may be weakly linked with type II fiber areas, only in females with high-power profiles.

The importance of protein intake in master marathon runners.

OBJECTIVES: The aim of this study was to investigate the relationships between protein intake (during the tapering period and the race), marathon performance, body composition, acute race-induced changes, and selected metabolic- and muscle damage-related blood biomarkers in recreational master runners. METHODS: In 58 experienced master runners (58.28 y ± 1.07 y, 174.06 cm ± 0.72 cm, 78.51 kg ± 0.76 kg body mass, 21.38% ± 0.52% body fat, mean ± SEM), nutritional intake was evaluated 1 wk before the race and during the marathon. Body composition was evaluated before and 2 h after the race. Blood samples were collected at the same time points. RESULTS: Body fat and lean body mass (LBM) were significantly reduced after the marathon (P < 0.01; η2: 0.311-0.888). Significant negative correlations were observed between energy intake from carbohydrates and proteins (expressed per LBM), marathon performance, and race-induced changes of blood metabolic-muscle damage indices (P < 0.05; r: -0.522 to -0.789). Positive correlations were observed between energy from carbohydrates and proteins per LBM, and body mass and LBM changes (P < 0.05; r: 0.485-0.814). The specific contribution of protein intakes per LBM (beta coefficient: -0.789 to 0.615) on race-induced changes of body composition and blood markers was the same as that of carbohydrate intakes per LBM (beta coefficient: -0.777 to 0.559). CONCLUSIONS: Marathon-induced changes in body composition and metabolic blood indices are highly related to protein intake, either during the tapering period or during the race, with runners experiencing the lowest changes when consuming higher protein intakes.

Can Exercise-Induced Muscle Damage Be a Good Model for the Investigation of the Anti-Inflammatory Properties of Diet in Humans?

Subclinical, low-grade, inflammation is one of the main pathophysiological mechanisms underlying the majority of chronic and non-communicable diseases. Several methodological approaches have been applied for the assessment of the anti-inflammatory properties of nutrition, however, their impact in human body remains uncertain, because of the fact that the majority of the studies reporting anti-inflammatory effect of dietary patterns, have been performed under laboratory settings and/or in animal models. Thus, the extrapolation of these results to humans is risky. It is therefore obvious that the development of an inflammatory model in humans, by which we could induce inflammatory responses to humans in a regulated, specific, and non-harmful way, could greatly facilitate the estimation of the anti-inflammatory properties of diet in a more physiological way and mechanistically relevant way. We believe that exercise-induced muscle damage (EIMD) could serve as such a model, either in studies investigating the homeostatic responses of individuals under inflammatory stimuli or for the estimation of the anti-inflammatory or pro-inflammatory potential of dietary patterns, foods, supplements, nutrients, or phytochemicals. Thus, in this review we discuss the possibility of exercise-induced muscle damage being an inflammation model suitable for the assessment of the anti-inflammatory properties of diet in humans.