Fear of failure in Brazilian runners

This study aims to investigate the fear or failure (FoF) in Brazilian runners of both sex, performance levels and age categories, as well as to verify the relationship between FoF and socioeconomic status (SES). Sample size as composed by 916. Age, sex, body height, body weight, SES, and running pace were self-reported. The Multidimensional Questionnaire of FoF was applied in an online platform. Running pace, and SES were categorized and processed through multivariate analysis and Spearman correlations, with the p-value set at 0.05. Female runners with better performance (2.13 ± 0.74) and younger (2.16 ± 0.80), as a well as male runners with worse performance (2.04 ± 0.69) and older (2.04 ± 0.89) presented the highest values of FoF. Among women, SES was negatively associated with FoF (r = -0.144; p = 0.006), while a positive association between running pace and SES was observed among men (r = 0.290; p < 0.001). Non-professional Brazilian runners presented low values of FoF.

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.

Acute effect of hydrogen-rich water on physical, perceptual and cardiac responses during aerobic and anaerobic exercises: a randomized, placebo-controlled, double-blinded cross-over trial

Molecular hydrogen (H2 gas) dissolved in water to produce Hydrogen-Rich Water. Hydrogen-Rich Water (HRW) is considered as ergogenic aid in different exercise modes. However, acute pre-exercise HRW ingestion effect is unclear regarding athlete performance. This study aimed at investigating acute effect of HRW ingestion on aerobic and anaerobic exercise performance. Twenty-two male amateur middle-distance runners volunteered to participate in this study. In a randomized, double-blind study design, all players ingested 500 mL of HRW or placebo (PLA) supplement 30 min before the start of the tests. Over 4 days, maximal aerobic speed of Vameval test (MAS), time to exhaustion at MAS (Tlim), squat jump (SJ), counter-movement jump (CMJ) and five jump test (5JT) were evaluated. Also, rate of perceived exertion (RPE) and peak heart rate (HRpeak) were measured during the aerobic tests. For Vameval test, HRW ingestion improved MAS, HRpeak and RPE compared with the placebo condition. For Tlim test, HRW ingestion demonstrated improvements in time to exhaustion, RPE and HRpeak. However, no significant change was observed between HW and placebo conditions in SJ, CMJ, 5JT. 500 mL of HRW can significantly improve HRpeak, time to exhaustion, RPE, with no significant effect on MAS, jumping performance in amateur endurance athletes.

Normative reference and cut-offs values of maximal aerobic speed-20 m shuttle run test and maximal oxygen uptake for Tunisian adolescent (elite) soccer players

This study aimed to develop reference curves of aerobic parameters of 20 m shuttle run test for Tunisian soccer players. The study was conducted in the 2022/2023 pre-season. The reference curves of the maximal aerobic speed (MAS) and the maximal oxygen uptake (VO2max) were developed according to the Lambda, Mu and Sigma (LMS) method, using data from 742 Tunisian premier league soccer players aged 11-18 years. Measured variables included: weight, height, body mass index and maximal heart rate (HRmax). HRmax was measured when the participants completed the maximal aerobic speed. VO2max was estimated using the 20 m shuttle run test protocol (speed increment every minute). Our results presented the smoothed percentiles (3rd, 10th, 25th, 50th, 75th, 90th and 97th) of MAS (km/h) and VO2max (ml/kg•min⁻1) according to age. In addition, raw data showed that VO2 max was positively correlated with age (r = 0.333; P < 0.001), height (cm) (r = 0.279; P < 0.001), weight (kg) (r = 0.266; P < 0.001), practice period (years) (r = 0.324; P < 0.001) and BMI (kg/m2) (r = 0.10; P < 0.05). However, it was negatively correlated to HRmax (bpm) (r = -0.247; P < 0.001). Only the measurements within the age group [12-12.99] are significantly higher (p < 0.001; ES = 0.63) compared with the previous age group [11-11.99]. Finally, regarding prevalence, our findings showed that 15.5 % of the players in our sample had VO2max values above the 87.7th percentile cut-off, while only 0.3 % exceeded the 99.18th percentile. The development of normative curves could help coaches and physical trainers to more accurately detect weaknesses in the aerobic performance of their players in order to sustain high-intensity repetitive actions during a soccer match.

Single and Combined Effects of Preferred Music and Endpoint Knowledge on Jump Performance in Basketball Players

Both music and endpoint knowledge of exercise have been shown to independently influence exercise performance. However, whether these factors work as synergists or counteract one another during exercise is unknown. The purpose of this study was to determine the single and combined effect of listening to preferred music and types of endpoint knowledge on repeated countermovement jump (CMJ) test performance. Twenty-four (n = 24) current or previously competitive basketball players underwent CMJ testing under the following endpoint knowledge conditions: (1) unknown/no knowledge, (2) knowledge of the number of jumps, and (3) knowledge of exercise duration. For each of these, participants listened to either their preferred music or no music during the duration of testing. For the exercise portion, participants completed repeated CMJs where participants were encouraged to jump as high as possible with jump height, contact time, and flight time as outcomes. Rate of perceived exertion (RPE) and feeling scale were measured before and after exercise. The results showed that, regardless of knowledge type, preferred music resulted in a significant decrease in both contact time and flight time (F ≥ 10.4, p ≤ 0.004, and η_p² ≥ 0.35), and a significant improvement of jump height (F = 11.36, p = 0.001, and η_p² = 0.09) and feeling scale ratings (F = 36.9, p < 0.001, and η_p² = 0.66) compared to no-music condition, while RPE was not significantly affected. Regardless of the presence of music, knowledge of the number of jumps and duration resulted in lower contact time (p < 0.001, 0.9 < d < 1.56) versus unknown condition during CMJs. Moreover, a significant decrease in RPE values was found during prior endpoint knowledge of number (p = 0.005; d = 0.72) and duration (p = 0.045; d = 0.63) compared to unknown condition. However, feeling scale ratings were not significantly affected. Moreover, no interactions with significance findings were found for any parameters. Overall, data suggest that listening to music and endpoint knowledge alter exercise responses in basketball players, but they do not interact with one another.

Effects of moderate- vs. high-intensity interval training on physical fitness, enjoyment, and affective valence in overweight/obese female adolescents: a pre-/post-test study

OBJECTIVE

The aim of this study was to compare the effects of 12-week moderate-intensity interval training (MIIT) vs. high-intensity interval training (HIIT) on body composition, physical fitness, and psychological valence in overweight/obese (OW/OB) female adolescents.

PATIENTS AND METHODS

Thirty-eight OW/OB female students were randomized into HIIT (n=13), MIIT (n=13) or control (n=12) groups. The participants underwent a 12-week interval-training program at 100% to 110% and 60% to 75% of maximal aerobic speed for HIIT and MIIT, respectively. The control group kept their usual physical activity without completing the training program. Pre- and post-training measurements were performed to assess body composition, aerobic capacity, and anaerobic performance (using selected tests evaluating speed, jumping ability, and strength). Ratings of perceived exertion and the feeling scale were evaluated every three weeks. Enjoyment was measured at the end of the program. A two-way analysis of variance with repeated measurements was applied to test for "group×time" interactions for body composition, physical fitness, and affective variables.

RESULTS

Significant "group×time" interactions were detected for aerobic and anaerobic performance, body composition indices, and the feeling scale. HIIT resulted in more noticeable improvements in body composition and physical performance than MIIT, while no significant changes were found in the control group. Throughout the program, the feeling score has progressively increased in the MIIT group but decreased in the HIIT group. Ratings of the perceived exertion have increased in both groups, more noticeably in the HIIT group. At the end of the program, the MIIT group showed a higher enjoyment score.

CONCLUSIONS

Despite offering better body composition improvement and physical fitness enhancement, HIIT offered lesser enjoyment and affective valence than MIIT in OW/OB female adolescents. MIIT might be an alternative time-efficient protocol for improving health in this population.

Listening to music during a repeated sprint test improves performance and psychophysiological responses in healthy and physically active male adults

BACKGROUND

It is well-documented that listening to music has the potential to improve physical performance during intense physical exercise. Less information is available on the timing of music application. This study aimed to investigate the effects of listening to preferred music during the warm up of a subsequent test or during the test on performance of repeated sprint sets (RSS) in adult males.

METHODS

In a randomized cross-over design, 19 healthy males (age, 22.1 ± 1.2 years; body mass, 72.7 ± 9.3 kg; height, 1.79 ± 0.06 m; BMI, 22.6 ± 2.2 kg m^-2) performed a test including 2 sets of 5*20-m repeated-sprints under one of three conditions: listening to preferred music during the test; listening to preferred music during the warm-up; or not listening to music. The assessed parameters comprised RSS performance indices, blood lactate, heart rate, the pacing strategy profile, rating of perceived exertion, and a feeling scale.

RESULTS

For performance indices during set 1 of the RSS test, we found a significant decrease in total sum sequence, fast time index and fatigue index in the listening to preferred music condition compared to the no music condition (total sum sequence: p = 0.006, d = 0.93; fast time index: p = 0.003, d = 0.67; fatigue index: p < 0.001; d = 1.30) and the listening to preferred music during the warm-up condition (fast time index: p = 0.002; d = 1.15; fatigue index: p = 0.006; d = 0.74). However, there was no significant effect of listening to preferred music on physical performance during set 2 of the RSS test. Compared to the no music condition, blood lactate concentrations were higher in the listening to preferred music during the test condition (p = 0.025; d = 0.92). In addition, listening to preferred music appears not to have an effect on heart rate, the pacing strategy profile, perceived exertion, and affective responses before, during and after the RSS test.

CONCLUSION

Findings from this study revealed that RSS performances were better (FT and FI indices) in the PMDT compared with the PMWU condition. Moreover, in set 1 of the RSS test, better RSS indices were found in the PMDT compared to NM condition.

A macro to micro analysis to understand performance in 100-mile ultra-marathons worldwide

The purposes of this study were (i) to describe differences in participation in 100-mile ultra-marathons by continent; (ii) to investigate differences in performance between continents; and (iii) to identify the fastest runners by continent and country. Data from 148,169 athletes (119,408 men), aged 18-81 years, and finishers in a 100-miles ultra-marathon during 1870-2020 were investigated. Information about age, gender, origin, performance level (top three, top 10, top 100) was obtained. Kruskal-Wallis tests and linear regressions were performed. Athletes were mostly from America and Europe. A macro-analysis showed that the fastest men runners were from Africa, while the fastest women runners were from Europe and Africa. Women from Sweden, Hungary and Russia presented the best performances in the top three, top 10 and top 100. Men from Brazil, Russia and Lithuania were the fastest. The lowest performance and participation were observed for runners from Asia. In summary, in 100-miles ultra-marathon running, the majority of athletes were from America, but for both sexes and performance levels, the fastest runners were from Africa. On a country level, the fastest women were from Sweden, Hungary and Russia, while the fastest men were from Brazil, Russia and Lithuania.

How to end up on the podium after running a 6-days-run with type 1 diabetes mellitus - A case study and literature review

BACKGROUND

An increasing number of people living with type 1 diabetes mellitus (T1DM) are pushing their physical limits to compete at the sport's highest level. Muscle, liver, and glycogen metabolism can be normal in athletes with diabetes with good glucose management, and modifications to insulin dose and nutrition can facilitate exercise performance.

CASE PRESENTATION

We report on a 66-year-old runner with insulin-dependent T1DM. He has run over 90 marathons and ultra-marathons. Thanks to an insulin pump and continuous glucose monitoring, he has completed forty-eight 24-hour runs with an average performance of 133.8 km. Over the years, the runner increased his monthly running volume significantly and decreased his glycated Hemoglobin type A1C (hba1c) levels. Meanwhile, a significant association between monthly running kilometers and hba1c levels could be shown. At the age of 66 years, he finished his sixth 6-day-run in third place overall by covering a total distance of 467.424 km.

CONCLUSIONS

These findings show that it is possible to participate in ultra-endurance events while suffering from T1DM without glucose derailing. With a good understanding of the disease and its impact on an individual's body, we can curtail the preparation and execution phases of ultra-endurance events to allow athletes to compete with minimal risk.

The relationship between lower limb muscle volume and peak vertical jump power in children

BACKGROUND: Vertical jump is an index representing leg power. It is important to determine factors that influence the vertical jump to help athletes improve their leg power. OBJECTIVE: This study aimed to determine the relationship between lower limbs muscle volume and peak vertical jump (VJ) power in children for both sexes. METHODS: Fourty children healthy boys (n= 20) and girls (n= 20) aged 10 to 12 years old, randomly performed three VJ modalities: squat jump (SJ), counter movement jump without (CMJ) and with arm swings (CMJarms). Lower limbs muscle volume (MV) estimated using a standard anthropometric method. Peak power (PP) calculated by Sayers equation. RESULTS: significant correlations between MV and Peak vertical jump power showed for both sexes. Likewise, significant correlations were found between MV and body mass for boys (r= 0.66; p= 0.001) and for girls (r= 0.59; p= 0.006). CONCLUSIONS: The correlation observed between peak vertical jump power and MV in both sexes can be considered as estimation tool of the lower limbs muscle power. Lower limb’s muscle volume are determining factor in muscle power for both sexes.

Effects of High-Intensity Interval Training on Selected Adipokines and Cardiometabolic Risk Markers in Normal-Weight and Overweight/Obese Young Males-A Pre-Post Test Trial

The study aimed to assess effects of high-intensity interval training (HIIT) on plasma adipokines and cardiometabolic markers in normal and excess weight youth. Eighteen healthy young males (18.2 ± 1.06 yrs.) were divided in normal-weight group (NWG; body mass index (BMI), 20.5 ± 1.51 kg/m2; n = 9) and excess-weight group (EWG; BMI, 30.8 ± 4.56 kg/m2; n = 9). Participants performed an eight-week HIIT program without caloric restriction. Body composition, plasma leptin, adiponectin, chemerin, omentin-1, lipids, C-reactive protein (CRP), and the homeostasis model assessment index for insulin resistance (HOMA-IR) were assessed before and after the HIIT program. The program resulted in significant increases in omentin levels (p < 0.01) in EWG (27%) and NWG (22%), but no changes in leptin, adiponectin, and chemerin in both groups. BMI (−1.62%; p = 0.015), body fat (−1.59%; p = 0.021), total cholesterol (−11.8%; p = 0.026), triglycerides (−21.3%; p = 0.023), and HOMA-IR (−31.5%; p = 0.043) decreased in EWG only. Repeated measures detected significant interaction “Time x Group” for body mass and BMI only. Eight-week HIIT program improved body composition, lipid profile, and insulin sensitivity in excess-weight individuals. It resulted in an increase in omentin levels in both normal- and excess-weight groups, but no changes in leptin, adiponectin, and chemerin. Body composition has not influenced the response of the four adipokines to HIIT.

Effect of two incremental intensity field tests on wellness indices, recovery state, and physical enjoyment in soccer players

OBJECTIVE

Competitive athletes must undergo fitness testing to monitor athlete progress and to create appropriate, progressive training programs. However, fitness testing adds to training stress; therefore, impacts of testing on wellness and recovery must be considered in test selection. This study investigated the effects of two incremental field tests [VAMEVAL test (T-VAM) and 20-m maximum shuttle test (20-m MST)] on wellness, total quality of recovery (TQR) and physical enjoyment (PE) in competitive soccer players.

SUBJECTS AND METHODS

Twenty-two soccer players (20.9±1.5 years) completed two T-VAM and two 20-m MST in a randomized order on separate days with a 1-week interval between tests. TQR and wellness indices (sleep, fatigue, stress and muscle soreness) measures were collected before and 24 hours after each test. Heart rate (HR) was continuously monitored during each test. Rating of perceived exertion (RPE) and PE were assessed after each test.

RESULTS

T-VAM resulted in higher PE, TQR and wellness scores than 20-m MST (p<0.05). T-VAM and 20-m MST resulted in similar HR and maximal aerobic speed. For T-VAM, TQR was correlated (p<0.01) with RPE and wellness indices. For 20-m MST, TQR was correlated (p<0.01) with wellness indices. HRmax and RPE were not correlated with wellness indices, TQR or PE.

CONCLUSIONS

Overall, T-VAM and 20-m MST produced similar aerobic fitness testing results, but athletes responded more favorably to T-VAM. Coaches can use T-VAM for evaluating aerobic fitness while maximizing well-being and physical enjoyment among soccer players.

The Effects of Verbal Encouragement and Compliments on Physical Performance and Psychophysiological Responses During the Repeated Change of Direction Sprint Test

The general and sports psychology research is limited regarding the difference between the effects of verbal encouragement (VE) or compliment methods during high-intensity functional exercise testing. The purpose of this study was to explore the effects of VE and compliments on the performance of the repeated change-of-direction (RCOD) sprint test. A total of 36 male students in secondary school participated voluntarily in the study. They were divided equally into three homogeneous groups [VE group, compliment group (CG), and control group) and performed a standardized one repetition RCOD. The RCOD (6 × 20 m with 25-s active recovery) test consisted of a 100°change in the direction at every 4 m. Outcomes included performance indices (fast time, average time, and total time), rating of perceived exertion (RPE), and feeling scale scores. VE and the compliment increased the performance indices and RPE compared with the control group. In conclusion, VE during the exercise testing would be more beneficial for optimal performance and RPE compared with the compliment and control groups. However, the moods, during RCOD, reproduce more positively during compliment conditions than the VE and control groups.

The Sex Difference in 6-h Ultra-Marathon Running—The Worldwide Trends from 1982 to 2020

Background and Objectives: The 6-h ultra-marathon is the shortest time-limited ultra-marathon race, but little has been investigated regarding this race format. Previously, only the age of peak performance in the context of longer time-limited ultra-marathons was determined. The purpose of this study was to investigate the trends in 6-h ultra-marathon races from 1982 to 2020 for female and male ultra-runners, the participation and performance by countries, the age of peak performance, and the differences in performance regarding countries. Materials and Methods: The sample included 23,203 female ultra-runners, aged 18–83 years, and 87,264 male ultra-runners, aged 18–85 years, who were finishers in a 6-h ultra-marathon held between 1982 and 2020. The age of peak performance was tested using the Kruskal–Wallis test, followed by the Bonferroni Correction. The difference in performance by countries was verified using a linear regression model with the fastest runners from Russia in women, and Tunisia in men, used as reference. Results: Over the years, the men-to-women ratio decreased. The mean age was 43.20 ± 9.30 years for female and 46.09 ± 10.17 years for male runners. Athletes in younger age groups were faster than athletes in older age groups. Most female and male participants originated from Germany. Women from Russia (10.01 ± 1.28 km/h) and men from Tunisia (12.16 ± 1.46 km/h) were the fastest. Conclusions: In summary, in 6-h ultra-marathons held between 1982 and 2020, the participation for both women and men increased, while the men-to-women ratio decreased. The mean age was higher in men compared to women. Most female and male runners originated from Germany, but the fastest women were from Russia, and the fastest men from Tunisia. Future studies need to investigate whether Russian women and Tunisian men are also the best in other distance-limited ultra-marathon races, such as 12-h and 24-h.

Interval Training with Different Intensities in Overweight/Obese Adolescent Females

To compare the effects of 12 weeks of high-intensity interval training (HIIT) versus moderate-intensity interval training (MIIT) on hematological and inflammatory markers in youth females, 38 overweight/obese females (16.4±1.0 yrs.) were randomly assigned to HIIT (2×6-8 repetitions of 30 s at 100-110% maximal aerobic speed (MAS), with 30 s active recovery between repetitions at 50% MAS; n=13), MIIT (2×6-8 repetitions of 30 s at 70-80% MAS, with 30 s active recovery between repetitions at 50% MAS; n=13), and a control group (CG, no intervention; n=12). Body composition, blood pressure, maximal heart rate, hematological and inflammatory markers (C-reactive protein [CRP], and erythrocyte sedimentation rate [ESR]) markers were assessed in all groups before and following the training program. Results revealed a significant (P<0.05) interaction effect for body composition, systolic blood pressure (SBP), MAS, maximal heart rate, and CRP. Within-group analyses for the HIIT and MIIT groups showed significant improvements in body mass (P=0.009 and P=0.025, respectively), BMI Z-score (P=0.011 and P=0.028, respectively), and MAS (P<0.001 and P=0.011, respectively). The HIIT program showed a significant decrease in body fat (P=0.002), waist circumference (P=0.002), maximal heart rate (P=0.003), SBP (P=0.001), and plasma CRP (P=0.004). In both groups, no significant changes were observed in ESR and hematological markers after intervention. No variable changed in CG. HIIT was the effective method to manage cardiometabolic health and inflammatory disorders in obese youth.

Ghrelin Response to Acute and Chronic Exercise: Insights and Implications from a Systematic Review of the Literature

BACKGROUND

Ghrelin is a peptide hormone predominantly produced by the stomach. It exerts a wide range of functions including stimulating growth hormone release and regulating appetite, food intake, and glucose and lipid metabolism. Since physical exercise affects all these aspects, a particular interest is accorded to the relationship between ghrelin and exercise. This systematic review aimed to summarize the current available data on the topic for a better understanding of the relationship.

METHODS

An extensive computerized search was performed in the PubMed and SPORTDiscus databases for retrieving relevant articles. The search contained the following keywords: ghrelin, appetite-related peptides, gastrointestinal peptides, gastrointestinal hormones, exercise, acute exercise, chronic exercise, training, and physical activity. Studies investigating the effects of acute/chronic exercise on circulating forms of ghrelin were included.

RESULTS

The initial search identified 840 articles. After screening, 80 articles were included. Despite a heterogeneity of studies and a variability of the findings, the review suggests that acute exercise suppresses acyl ghrelin production regardless of the participants and the exercise characteristics. Long- and very long-term exercise training programs mostly resulted in increased total and des-acyl ghrelin production. The increase is more noticeable in overweight/obese individuals, and is most likely due to weight loss resulting from the training program.

CONCLUSION

The review suggests that exercise may impact ghrelin production. While the precise mechanisms are unclear, the effects are likely due to blood flow redistribution and weight loss for acute and chronic exercise, respectively. These changes are expected to be metabolically beneficial. Further research is needed for a better understanding of the relationship between ghrelin and exercise.

Greater effects of high- compared with moderate-intensity interval training on thyroid hormones in overweight/obese adolescent girls

OBJECTIVES

To investigate the effects of 12-week high-intensity- (HIIT) vs. moderate-intensity-interval training (MIIT) on thyroid stimulating hormone (TSH) and thyroxine (T4) and insulin-resistance in overweight/obese adolescent girls.

METHODS

Twenty four adolescent girls (age 16.5±1.36 yrs) were randomly allocated into three groups: (1) HIIT (2 blocks per session of 6-8 bouts of 30 s runs at 100-110% maximal aerobic speed (MAS), with 30 s active recovery between bouts at 50% MAS; n=8), (2) MIIT (2 blocks per session of 6-8 bouts of 30 s runs at 70-80% MAS, with 30 s active recovery between bouts at 50% MAS; n=8) and (3) control group (no exercise, n=8). Each training groups engaged in three sessions per week during three months. Anthropometric parameters, aerobic capacity, homeostasis model assessment index for insulin resistance (HOMA-IR) as well as plasma TSH and T4 levels were assessed in all subjects before- and after-training.

RESULTS

Following both training programs, body mass, body mass index Z-score, waist circumference and body fat decreased, while aerobic capacity increased. However, TSH and T4 concentrations decreased only after the HIIT (-30.47%, p<0.05, ES=1.42 and -12.86%, p<0.05, ES=1.18; respectively). The HOMA-IR decreased in both training groups (-26.25%, p<0.05, ES=1.87 for MIIT and -21.72%, p<0.05, ES=2.14 for HIIT).

CONCLUSION

Twelve weeks of HIIT was effective in reducing circulating TSH and T4 levels, unlike MIIT, in overweight/obese adolescent girls. These findings indicated that the stimulation of pituitary-thyroid function is more sensitive to training intensity than training duration. Further studies are needed to confirm this conclusion.

Association of selected adipokines with metabolic syndrome and cardio-metabolic risk factors in young males

The study aimed to investigate association of circulating leptin, adiponectin, chemerin, and omentin-1 with metabolic syndrome (MetS) and cardio-metabolic risk factors in youths. Thirty eight young males were enrolled. Participants underwent anthropometric and blood pressure measures, and fasting blood sampling. Plasma leptin, adiponectin, chemerin, omentin-1 and insulin were measured by ELISA methods. Multiple linear regression models, adjusting for age, MetS traits, C-reactive protein (CRP) and homeostasis model assessment of insulin resistance (HOMA-IR), were applied to determine correlates for each adipokine. Eleven participants meet criteria of MetS. These individuals had higher leptin and chemerin and lower adiponectin plasma concentrations than those without MetS. Plasma leptin and chemerin were positively related, and adiponectin and omentin-1 were inversely related to cardio-metabolic traits. In multivariate models, predictors of leptin were age (β, 0.20, P = 0.01), abdominal obesity (β, 0.24, P = 0.06), raised blood pressure (β, 0.40, P = 0.01), raised triglycerides (β, 0.19, P = 0.01) and CRP (β, 0.31, P = 0.01). Chemerin was associated with abdominal obesity (β, 0.33, P = 0.09) and CRP (β, 0.29, P = 0.04), and adiponectin was associated with raised triglycerides (β, -0.26, P = 0.05), decreased HDL-C (β, -0.28, P = 0.06) and CRP (β, -0.48, P = 0.01). HOMA-IR (β, -0.39, P = 0.09) was the only predictor for omentin. MetS is associated with an altered plasma adipokines profile, with increased leptin and chemerin and decreased adiponectin circulating levels. These findings suggest a beneficial potential of adiponectin and omentin, but a detrimental potential of leptin and chemerin. Further research is needed to lighten the role of adipose tissue-derived adipokines in cardio-metabolic health.

SMALL SIDED GAMES VS REPEATED SPRINT TRAINING EFFECTS ON AGILITY IN FASTING BASKETBALL PLAYERS

ABSTRACT Introduction The coinciding of month of Ramadan with international basketball competitions could affect players’ performance. Objective This field investigation examined the impacts of a basic training program in small-sided games and repeated sprint ability during intermittent fasting for Ramadan (R) and one month after Ramadan (AR) [control month] on body composition, agility and lower limb power. Methods Sixteen basketball players (age, 23.4±2.3 years) performed two training programs [small-sided games (SSG) and repeated sprint ability (RSA)] during R and AR, interrupted by fifteen days of total recovery. The players were randomly allocated to two groups (GSSG, n=8 and GRSA, n=8). Body composition, agility T test, squat jump (SJ) test, countermovement jump (CMJ) test and five-jump (FJT) test performances were measured on four occasions: before R (P1) and at the end of R (P2),as well as before AR (P3) and at the end of AR (P4). Results The results showed that body mass (BM), body mass index (BMI) and body fat (BF %) decreased significantly at the end of R for both groups (all p < 0.001). Moreover, the performances in the agility T test, SJ test, CMJ test and FJT test improved significantly at the end of R for both groups (p<0.001 and p<0.01). Also, by comparing R with the control month, we recorded significantly better agility and FJT performances in the R month (p < 0.001). Conclusions This study indicated that Ramadan combined with RSA and SSG training may improve agility and lower limb power, enabling coaches and physical trainers to choose between these two training modalities, depending on the training objectives. Level of evidence II; Diagnostic Studies - Investigating a diagnostic test.

Continuous Moderate-Intensity but Not High-Intensity Interval Training Improves Immune Function Biomarkers in Healthy Young Men

Khammassi, M, Ouerghi, N, Said, M, Feki, M, Khammassi, Y, Pereira, B, Thivel, D, and Bouassida, A. Continuous moderate-intensity but not high-intensity interval training improves immune function biomarkers in healthy young men. J Strength Cond Res 34(1): 249-256, 2020-Effects of endurance running methods on hematological profile are still poorly known. This study aimed to compare the effects of 2 training regimes; high-intensity interval training (HIIT) and moderate-intensity continuous training (MCT) performed at the same external load on hematological biomarkers in active young men. Sixteen men aged 18-20 years were randomly assigned to HIIT or MCT group. Aerobic capacity and hematological biomarkers were assessed before and after 9 weeks of interventions. At baseline, aerobic and hematological parameters were similar for the 2 groups. After intervention, no significant change was observed in maximal aerobic velocity and estimated VO2max in both groups. Leukocyte (p < 0.01), lymphocyte (p < 0.05), neutrophil (p < 0.05), and monocyte (p < 0.01) count showed significant improvements in response to the MCT compared with the HIIT intervention. The MCT intervention favored an increase in the number of immune cells, whereas the opposite occurred as a result of the HIIT intervention. These findings suggest that MCT interventions might be superior to HIIT regimes in improving immune function in active young men.

A single mega dose of vitamin D3 improves selected physical variables in vitamin D-deficient young amateur soccer players: a randomized controlled trial

This randomized controlled trial aimed to test whether vitamin D (VD) supplementation affects measures of physical performance in VD-deficient, mildly trained children. Thirty-six recreationally soccer player boys were randomly assigned to single dose (200 000 IU) of VD3 (n = 19) or placebo (n = 17). Plasma 25-hydroxyvitamin D (25-OHD) was assessed and measures of physical performance (i.e., vertical and standing broad jumps, triple hop, 10-m and 30-m sprints, shuttle run) were performed before and 12 weeks after the loading dose. Mixed ANCOVA models were performed and effect size was estimated by partial eta squared (η_p²). Baseline 25-OHD and physical variables were equivalent in the 2 groups. Twelve weeks after VD loading, plasma 25-OHD increased and physical variables improved only in the VD group. There was a significant interaction effects for group by time for vertical jump (F = 14.9, p = 0.001, η_p² = 0.394), triple hop jump (F = 24.2, p < 0.001, η_p² = 0.513), 10-m (F = 4.46, p = 0.046, η_p² = 0.162) and 30-m (F = 6.56, p = 0.017, η_p² = 0.222) sprints, and shuttle run (F = 13.4, p = 0.001, η_p² = 0.369). In conclusion, a single bolus of VD3 resulted in significant improvements in jumping ability, agility, and running speed in mildly trained children that are deficient in VD. The findings suggest that correcting VD deficit might be beneficial for physical performance. Novelty A mega dose of VD3 improves jumping ability, agility, and running speed in VD-deficient, mildly trained children. Effect of VD on measures of physical performance is noticeable 3 months after the loading dose.

Effects of Recovery Mode during High Intensity Interval Training on Glucoregulatory Hormones and Glucose Metabolism in Response to Maximal Exercise

Catecholamines [adrenaline (A) and noradrenaline (NA)] are known to stimulate glucose metabolism at rest and in response to maximal exercise. However, training and recovery mode can alter theses hormones. Thus our study aims to examine the effects of recovery mode during High-intensity Interval Training (HIIT) on glucoregulatory hormone responses to maximal exercise in young adults. Twenty-four male enrolled in this randomized study, assigned to: control group (eg, n=6), and two HIIT groups: intermittent exercise (30 s run/30 s recovery) with active (arg, n=9) or passive (prg, n=9) recovery, arg and prg performed HIIT 3 times weekly for 7 weeks. Before and after HIIT, participants undergo a Maximal Graded Test (MGT). Plasma catecholamines, glucose, insulin, growth hormone (Gh) and cortisol were determined at rest, at the end of MGT, after 10 and 30 min of recovery. After training V0_2max and Maximal Aerobic Velocity (MAV) increased significantly (p<0.05) in arg. After HIIT and in response to MGT plasma glucose increase significantly (p=0.008) lesser in arg compared to prg whereas insulin concentrations were similar. The glucose/insulin ratio was significantly lower at MGT end (p=0.033) only in arg after training. After HIIT, in response to MGT, plasma A, NA, cortisol and Gh concentrations were significantly higher only in arg (p<0.05). HIIT using active recovery is beneficial for aerobic fitness, plasma glucose and glucoregulatory hormones better than HIIT with passive recovery. These findings suggest that HIIT with active recovery may improve some metabolic and hormonal parameters in young adults.

Impact of a 12-week high-intensity interval training without caloric restriction on body composition and lipid profile in sedentary healthy overweight/obese youth

Although High-intensity interval training (HIIT) has shown its effectiveness in improving body composition, cardio-respiratory fitness and lipid profile in obese adults, evidences remain limited in overweight/obese youth. This study was conducted to investigate the effect of a 12-week HIIT program without caloric restriction on body composition and lipid profile among young overweight/obese men. Twenty healthy obese youth were randomly allocated into two groups; experimental group (HIIT) and control group. The HIIT program consisted in 3 exercises sessions per week (30 sec of work at 100% maximal aerobic velocity [MAV]) interspersed by 30 sec of active recovery at 50% MAV, starting by 15 repetitions to reach 27 by the end of the program. Aerobic capacity (MAV and maximum oxygen uptake [VO2max]), body composition (body mass index [BMI], waist circumference [WC], and fat mass percent) and lipid profile (triglycerides [TG] and total, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol) were determined before and after the HIIT program. Following 12 weeks of HIIT, WC, BMI (P<0.01), and fat mass percent (P<0.05) were significantly decreased. MAV and VO2max were significantly improved in the HIIT group, only. Total cholesterol (P<0.05) and TG (P<0.05) decreased significantly in the HIIT group, while LDL and HDL cholesterol levels remained unchanged in both groups. HIIT may be particularly useful in overweight/obese youth to improve body composition, aerobic fitness and lipid profile.

Plasma chemerin in young untrained men: association with cardio-metabolic traits and physical performance, and response to intensive interval training

OBJECTIVES

Chemerin is an adipose tissue-derived adipokine thought to decrease insulin sensitivity and increase cardiometabolic risk. This study aimed to assess the association of chemerin with cardiometabolic risk and physical performance and examine its response to high-intensity interval training (HIIT).

METHODS

Eighteen young men have been applied a HIIT program during 8 weeks. Plasma chemerin together with several cardiometabolic factors and physical performance indices were determined before and after the training program. Plasma chemerin and insulin were assessed using immunoenzymatic methods. The homeostasis model assessment (HOMA-IR) index was calculated as an estimate of insulin resistance.

RESULTS

Basal plasma chemerin was positively correlated with body mass index (r=0.782, p<0.001), body fat (r=0.767, p<0.001), total (r=0.686, p=0.002) and LDL (r=0.587, p=0.010) cholesterol, triglycerides (r=0.775, p<0.001), HOMA-IR (r=0.673, p=0.002) and C-reactive protein (r=0.765, p<0.001). With regards to physical performance, chemerin was negatively correlated with maximal oxygen uptake (r=-0.572, p=0.013) and squat jump (r=-0.627, p=0.005), but positively related to 10-m sprint (r=0.716, p=0.001) and 30-m sprint (r=0.667, p=0.002) times. HIIT program resulted in significant improvements in body composition, plasma lipids and insulin sensitivity. However, no significant change was detected for plasma chemerin in response to HIIT (134±50.7 ng/mL vs. 137±51.9 ng/mL, p=0.750).

CONCLUSIONS

Basal plasma chemerin is associated with cardiometabolic health and physical performance in young men. Following HIIT, cardiometabolic health and physical performance had improved, but no significant change had occurred for plasma chemerin.

Effect of High-Intensity Interval Training on Plasma Omentin-1 Concentration in Overweight/Obese and Normal-Weight Youth

OBJECTIVES

Omentin-1 is a recently discovered adipokine, mainly produced by visceral adipose tissue, which is thought to improve insulin sensitivity. The study aimed to assess the association of plasma omentin-1 with cardiometabolic traits and physical performance and to test its response to high-intensity interval training (HIIT) in obese and normal-weight subjects.

METHODS

Nine overweight/obese (OG) and 9 normal-weight (NWG) young men performed an 8-week HIIT program. Body composition, physical performance, homeostasis model assessment index for insulin resistance (HOMA-IR) as well as plasma omentin-1and lipid levels were assessed before and after the HIIT program.

RESULTS

Baseline plasma omentin-1 was lower in OG than NWG men (359 ± 138 vs. 470 ± 114 ng/ml; p = 0.052). Plasma omentin-1 was related to body fat (r = -0.57; p = 0.03) and LDL-cholesterol (r = -0.49; p = 0.04). There was a trend towards significant association of omentin-1 with BMI (r = -0.47; p = 0.06) and VO2max (r = 0.41; p = 0.09). However, no association was observed with HOMA-IR. Following the HIIT program, omentin-1 concentrations have significantly (p < 0.01) increased in OG (359 ± 138 to 455 ± 126 ng/ml) and NWG men (470 ± 114 to 572 ± 115 ng/ml). In parallel, the cardiometabolic profile has improved with a significant decrease of HOMA-IR in OG.

CONCLUSIONS

HIIT resulted in a plasma omentin-1 increase and an improvement with regard to cardiometabolic traits in the OG men, which may contribute to modulate insulin sensitivity.

Vitamin D inadequacy is widespread in Tunisian active boys and is related to diet but not to adiposity or insulin resistance

BACKGROUND

Vitamin D inadequacy is widespread in children and adolescents worldwide. The present study was undertaken to assess the vitamin D status in active children living in a sunny climate and to identify the main determinants of the serum concentration of 25-hydroxyvitamin D (25-OHD).

METHODS

This cross-sectional study included 225 children aged 7-15 years practicing sports in a football academy. Anthropometric measures were performed to calculate body mass index (BMI), fat mass, and maturity status. A nutritional enquiry was performed including 3-day food records and food frequency questionnaire. Plasma 25-OHD and insulin were assessed by immunoenzymatic methods ensuring categorization of vitamin D status and calculation of insulin sensitivity/resistance indexes. A logistic regression model was applied to identify predictors for vitamin D inadequacy.

RESULTS

Vitamin D deficiency (25-OHD<12 µg/L) was observed in 40.9% of children and insufficiency (12<25-OHD<20 µg/L) was observed in 44% of children. In a multivariate analysis, vitamin D deficiency and insufficiency were associated with a lower dietary intake of vitamin D, proteins, milk, red meat, fish, and eggs. However, no significant relationship was observed with maturation status, adiposity, or insulin resistance.

CONCLUSIONS

Tunisian children and adolescents are exposed to a high risk of vitamin D inadequacy despite living in a sunny climate. Circulating 25-OHD concentrations are related to the intake of vitamin D food sources but not to maturation status or body composition. Ensuring sufficient and safe sun exposure and adequate vitamin D intake may prevent vitamin D inadequacy in children from sunny environments.

Effects of a high-intensity intermittent training program on aerobic capacity and lipid profile in trained subjects

BACKGROUND

Data regarding the effect of training on plasma lipids are controversial. Most studies have addressed continuous or long intermittent training programs. The present study evaluated the effect of short-short high-intensity intermittent training (HIIT) on aerobic capacity and plasma lipids in soccer players.

METHODS

The study included 24 male subjects aged 21-26 years, divided into three groups: experimental group 1 (EG1, n=8) comprising soccer players who exercised in addition to regular short-short HIIT twice a week for 12 weeks; experimental group 2 (EG2, n=8) comprising soccer players who exercised in a regular football training program; and a control group (CG, n=8) comprising untrained subjects who did not practice regular physical activity. Maximal aerobic velocity and maximal oxygen uptake along with plasma lipids were measured before and after 6 weeks and 12 weeks of the respective training program.

RESULTS

Compared with basal values, maximal oxygen uptake had significantly increased in EG1 (from 53.3±4.0 mL/min/kg to 54.8±3.0 mL/min/kg at 6 weeks [P<0.05] and to 57.0±3.2 mL/min/kg at 12 weeks [P<0.001]). Maximal oxygen uptake was increased only after 12 weeks in EG2 (from 52.8±2.7 mL/min/kg to 54.2±2.6 mL/min/kg, [P<0.05]), but remain unchanged in CG. After 12 weeks of training, maximal oxygen uptake was significantly higher in EG1 than in EG2 (P<0.05). During training, no significant changes in plasma lipids occurred. However, after 12 weeks, total and low-density lipoprotein cholesterol levels had decreased (by about 2%) in EG1 but increased in CG. High-density lipoprotein cholesterol levels increased in EG1 and EG2, but decreased in CG. Plasma triglycerides decreased by 8% in EG1 and increased by about 4% in CG.

CONCLUSION

Twelve weeks of short-short HIIT improves aerobic capacity. Although changes in the lipid profile were not significant after this training program, they may have a beneficial impact on health.