The impact of inactivity during the COVID-19 pandemic on the physical performance of high school athletes.

BACKGROUND/OBJECTIVE: This study was conducted during the 2019-2020 academic year to evaluate the impact of participation in school sports on students' Body Mass Index (BMI) and Assessing Levels of Physical Activity (ALPHA) test scores. Interrupted by the COVID-19 pandemic, which led to a suspension of in-person education, the study resumed in September 2021, refocusing on the effects of pandemic-induced inactivity on the physical fitness levels of the same cohort. METHODS: The study included twenty-nine male high school students (age: 17,24 ± 0,73 years), divided into thirteen athletes (participating in sports such as football, basketball, and track) and sixteen non-athletic counterparts. They underwent reassessment using the ALPHA test battery, evaluating cardiorespiratory, musculoskeletal, and motor skills fitness. Data were analyzed using independent and paired samples t-tests and a two-way repeated measures ANOVA to assess changes over time and between groups. Discriminant function analysis evaluated the ALPHA test's ability to classify students based on their athletic status pre- and post-pandemic. RESULTS: Initially, athlete students exhibited significantly better BMI, 20 m shuttle run, and 4 × 10 m speed run scores compared to their non-athlete peers. After the pandemic, only the 20 m shuttle run scores remained significantly higher for athletes, with diminished distinctions in other fitness areas. The classification accuracy of the ALPHA test battery decreased from 89.7 to 75.9% post-pandemic. CONCLUSION: The enforced sedentary lifestyle due to the COVID-19 pandemic adversely affected all students, particularly diminishing health-related fitness parameters such as body composition, cardiorespiratory and musculoskeletal strength, and motor skills. Students previously engaged in regular physical activity, notably school athletes, experienced significant fitness declines. This highlights the urgent need for targeted interventions to encourage active lifestyles among youth in the post-pandemic phase, aiming to avert long-term adverse health outcomes.

The contribution of energy systems during 30-second lower body Wingate anaerobic test in combat sports athletes: Intermittent versus single forms and gender comparison.

Combat sports, encompassing a range of activities from striking and grappling to mixed and weapon-based disciplines, have witnessed a surge in popularity worldwide. These sports are demanding, requiring athletes to harness energy from different metabolic pathways to perform short, high-intensity activities interspersed with periods of lower intensity. While it is established that the anaerobic alactic (ATP-PC) and anaerobic lactic systems are pivotal for high-intensity training sessions typical in combat sports, the precise contribution of these systems, particularly in varied training modalities such as single (SMT) and intermittent (IST) forms of the 30-second Wingate test, remains inadequately explored. This study aims at comparing performance outputs, physiological responses and gender differences during the SMT and IST forms of the 30-second Wingate test. Thirty-three highly trained combat sports athletes (17 women, 16 men; 10 boxing, 8 wrestling, 8 taekwondo and 7 karate) randomly performed SMT and IST. The IST consisted of three 10-second all-out attempts separated by 30 seconds of passive recovery, whereas the SMT was a single 30-second maximal effort. Resting, exercise and post-exercise oxygen uptake and peak blood lactate value were used to determine the metabolic energy demands via the PCr-LA-O2 method. The findings showed that total metabolic energy expenditure (TEE), ATP-PCr system contribution and the output of mechanical variables were higher in the IST than in the SMT form (all p<0.001). In contrast, the contribution of glycolytic and oxidative systems was higher in the SMT form (all p<0.001). However, exercise form and gender interaction were not significant (p>0.05). In combat sports, performance is not only determined by physiological and technical skills but also by metabolic energy input and efficiency. Therefore, our results can provide a comparison regarding the effects of exercise type and gender on metabolic energy metabolism to design the training of combat sports athletes.

Effects of Ramadan intermittent fasting on performance, physiological responses, and bioenergetic pathway contributions during repeated sprint exercise.

Introduction: This investigation aims to elucidate the impact of Ramadan intermittent fasting on performance, physiological responses, and bioenergetic pathway contributions during repeated sprints. Methods: Fourteen active male Muslim athletes (age = 22.4 ± 1.8 years, body weight = 69.5 ± 3.8 kg, height = 176 ± 5.1 cm) executed a repeated sprint protocol, consisting of ten 20-meter sprints with 15-s passive recovery intervals, during both fasting and non-fasting conditions. The fasting session was conducted after a 12-14 h fast following Sahur (the pre-dawn meal during Ramadan). In contrast, the non-fasting session occurred before the Ramadan fasting period began, during the same hours of the day, at a time when fasting was not yet required for the athletes. Bioenergetic pathway contributions during repeated sprints were quantified using the PCr-LA-O2 method. Results: The mean sprint time during fasting sessions was 3.4 ± 0.3 s compared to 3.3 ± 0.2 s in non-fasting sessions, indicating a trend approaching the threshold of significance for slower times in the fasted state (p = 0.052, effect size (ES) = 0.34). In terms of bioenergetic contributions, the total metabolic energy expenditure (TEE) was slightly lower during fasting sessions (236.5 ± 22 kJ) compared to non-fasting sessions (245.2 ± 21.7 kJ), but this difference was not statistically significant (p = 0.102, ES = 0.40). Similarly, metabolic energy expenditure per sprint was 23.7 ± 2.2 kJ in fasting conditions compared to 24.5 ± 2.2 kJ in non-fasting conditions (p = 0.106, ES = 0.35). The oxidative energy contribution did not differ significantly between fasting (34.2 ± 4.1 kJ) and non-fasting conditions (34.2 ± 4.1 vs. 35.5 ± 5.2 kJ; p = 0.238, ES = 0.28). Similarly, lactic (60.4 ± 7.6 vs. 59.2 ± 8.3 kJ; p = 0.484, ES = 0.15); and alactic (149.3 ± 19.9 vs. 143 ± 21.5 kJ; p = 0.137, ES = 0.30) energy contributions showed no significant differences between the fasting and non-fasting sessions. The percentage of performance decrement (Pdec) and the percentage contributions of oxidative, lactic, and alactic pathways to the total energy expenditure did not differ significantly between the fasting and non-fasting conditions, indicating a similar bioenergetic profile across both conditions. Conclusion: The present findings indicate no significant differences in performance metrics and metabolic outcomes between fasted and non-fasted states. Future assessments with longer duration and higher intensity protocols may provide further insights.

Validity and reliability of "My Jump app" to assess vertical jump performance: a meta-analytic review.

This systematic review and meta-analysis aims to investigate the validity and reliability of the My Jump smartphone application in measuring vertical jump height, specifically using flight-time-based measures. To identify potential studies for inclusion, a comprehensive search strategy was employed in PubMed, Web of Science, Scopus, and EBSCO host databases. Validity was assessed in two ways: (1) mean and standard deviations of My Jump measurements were compared to criterion methods to assess the agreement of raw scores; (2) correlation coefficients evaluated the within-group consistency of rankings between My Jump and criterion methods. Reliability was assessed using intraclass correlation coefficients (ICC). Heterogeneity was evaluated via Cochrane's Q statistic, its p-value, I2 value, and tau2 value. Publication bias was explored through funnel plot symmetry and confirmed with extended Egger's test. Following the search, 21 studies met the inclusion criteria. Results showed no significant difference in raw scores between My Jump and criterion methods, indicating high agreement. High correlation was also found for within-group rankings, suggesting consistency. The My Jump application demonstrated nearly perfect reliability scores. The My Jump application appears to be a valid and reliable tool for sports scientists and strength and conditioning practitioners, offering a cost-effective and accessible means for accurately assessing vertical jump performance in various settings. However, it should be noted that these results are specific to flight-time-based measures, and further research is needed to validate these findings against gold-standard take-off velocity methods.

Reliability and Validity of the Kickboxing Anaerobic Speed Test.

Purpose: This study investigated the test-retest reliability and discriminant validity of the Kickboxing Anaerobic Speed Test (KAST) and established a comparison with the maximal cycling sprint test (MCST). Methods: Forty-two male kickboxing athletes (18 elite and 24 sub-elite) participated in this study. Kickboxers performed the tests in both single and multiple forms. The KASTsingle was composed of kicks and punches, performed as quickly as possible until 5 reps of a 4 techniques' combination (i.e., straight left punch, right-roundhouse kick, straight right punch, and left-roundhouse kick) were completed. The MCSTsingle was composed by a single 6-s maximal effort. The KASTmultiple was performed using 5 sequential sets of the single form following a 10s rest interval between sets. The MCSTmultiple was performed using 5 × 6 s repeated cycling efforts with 10s rest intervals. The tests and retests were carried out on separate occasions. To establish the test's discriminatory capability, elite and sub-elite athletes were compared. Results: All tests' performance scores showed excellent relative and absolute reliability (ICC > 0.900, SEM ≤ 0.98 s for KASTs and ≤ 0.74 W•kg-1 for MCST tests). Significant correlations between the identical versions were "large" (r > 0.70). Receiving operating characteristic analyses indicated that the KASTs and cycling tests were able to effectively discriminate between elite and sub-elite kickboxers. Additionally, the findings showed that KASTsingle, MCSTsingle, KASTmultiple, and MCSTmultiple correctly classified the groups by 78.6%, 73.6%, 88.1%, and 78.6%, respectively. Conclusions: This study supported the test-retest reliability and the discriminant validity of the KASTsingle and KASTmultiple to evaluate kickboxing athletes.

Strength-Power Tests are More Effective When Performed After Exhaustive Exercise in Discrimination Between Top-Elite and Elite Wrestlers.

ABSTRACT: Özbay, S and Ulupinar, S. Strength-power tests are more effective when performed after exhaustive exercise in discrimination between top-elite and elite wrestlers. J Strength Cond Res 36(2): 448-454, 2022-This study aimed (a) to analyze strength-power variables in top-elite and elite wrestlers, (b) to identify which variables allow for discrimination between them, and (c) to investigate whether the results changed when the tests were performed after exhaustive exercise. Twenty-six male wrestlers who won medals at the national championship in junior or under-23 categories participated in this study. Athletes who also won medals at the European or World Championship were assessed as top-elite (n = 13), and others as elite (n = 13). Subjects performed the leg and arm Wingate anaerobic test (anaerobic power and capacity), maximum one repetition bench press and squat test (maximal dynamic strength), handgrip and leg strength test (isometric strength), vertical and horizontal jump test (muscle power), and pull-up and push-up (strength endurance) tests. The results showed that top-elite wrestlers produced a higher output in both lower-body and upper-body Wingate average power (relative) than the elite wrestlers when the tests were performed after full rest. However, top-elite wrestlers presented higher results (relative) in all tests, except vertical and horizontal jump tests, when the tests were performed after exhaustive exercise. Furthermore, in a discriminant function analysis, the groups were correctly classified at 65.4% when the tests were performed after full rest, whereas the groups were correctly classified at 92.3% when the tests were performed after exhaustive exercise. This study indicated that the strength-power tests performed after exhaustive exercise may be more effective in discriminating between top-elite and elite wrestlers.

Energy pathway contributions during 60-second upper-body Wingate test in Greco-Roman wrestlers: intermittent versus single forms.

This study aimed to investigate the energy pathway contributions and physiological and performance responses between a 10 × 6-second intermittent sprint test (IST) and a 60-second single maximal test (SMT). Seventeen highly trained male Greco-Roman wrestlers participated in this study. Participants completed the 60-second upper-body Wingate tests, both intermittent and single forms. The contributions of the oxidative, glycolytic, and ATP-PCr pathways were estimated using mathematical methods based on lactate values and oxygen consumption kinetics of rest, exercise, and recovery phases. The main findings indicated that total energy expenditure (TEE) and the contribution of oxidative, glycolytic, and ATP-PCr pathways were 514 kJ, 45%, 11%, and 44% for IST (overall: sprints + rest intervals); 333 kJ, 14%, 17%, and 69% for IST (sprints only); and 159 kJ, 31%, 38%, and 31% for SMT, respectively. TEE and ATP-PCR pathway contributions were higher in the IST (both overall and sprint only), whereas glycolytic pathway contribution and delta lactate were higher in the SMT. Absolute oxidative contribution was similar, but relative oxidative contribution was higher in the SMT. Additionally, mean power was higher in the IST than SMT, whereas peak power, peak and mean heart rate, and ratings of perceived exertion were similar.

Effect of Origanum dubium, Origanum vulgare subsp. hirtum, and Lavandula angustifolia essential oils on lipid profiles and liver biomarkers in athletes.

This study aims to determine the effects of essential oils of Origanum dubium (DUB), Origanum vulgare subsp. hirtum (HIR), and Lavandula angustifolia (LAV) on lipid profiles and liver biomarkers in athletes. Thirty-four trained athletes were randomly assigned to one of three experimental groups or the control group (CON). The concentrations of serum lipids and liver biomarkers were assessed before and after the 14-day essential oil intervention. Gas chromatography-mass spectrometry analysis showed 68.0 and 82.1% carvacrol in DUB and HIR, respectively, and 34.50% linalyl acetate and 33.68% linalool in LAV essential oils. One-way analysis of covariance (ANCOVA) indicated a significant difference (p = 0.001) among the groups for high-density lipoprotein cholesterol (HDL-C) when the associated preintervention values were used as a covariate. The related pairwise comparisons revealed that DUB (p = 0.001) and HIR (p = 0.024) had greater HDL-C values than CON. From the two-way ANOVA, an interaction between time (before vs. after) and the groups (DUB vs. HIR vs. LAV vs. CON) was found for HDL-C (p = 0.030). Findings indicated a significant increase in DUB (p = 0.0001) and HIR (p = 0.010) for HDL-C, and there was a significant decrease in DUB (p = 0.023) for low-density lipoprotein cholesterol. However, there was no difference in total cholesterol, triglycerides, and all liver biomarkers.

Performance Differences Between Greco-Roman and Freestyle Wrestlers: A Systematic Review and Meta-Analysis.

ABSTRACT: Ulupinar, S, Özbay, S, Gençoglu, C, and Ince, I. Performance differences between Greco-Roman and freestyle wrestlers: a systematic review and meta-analysis. J Strength Cond Res 35(11): 3270-3279, 2021-This systematic review and meta-analysis aims to summarize evidence on performance differences between Greco-Roman (GR) and freestyle (Fr) wrestlers. Eleven studies met the inclusion criteria (91 individual data and a total of 752 wrestlers). The analysis of handgrip strength comprised 9 outcomes from 5 studies with no significant difference between GR and Fr wrestlers. The analysis of isometric (back or leg) strength comprised 15 outcomes from 6 studies with a significant effect favoring GR wrestlers. The analysis of muscle power comprised 15 outcomes from 5 studies with a significant effect favoring GR wrestlers. The analysis of strength endurance comprised 4 outcomes from 3 studies with no significant difference between GR and Fr wrestlers. The analysis of anaerobic capacity and power comprised 6 outcomes from 3 studies with no significant difference between GR and Fr wrestlers. The analysis of speed comprised 19 outcomes from 7 studies with a significant effect favoring GR wrestlers. The analysis of flexibility comprised 20 outcomes from 6 studies with a significant effect favoring Fr wrestlers. This study indicated that GR wrestlers had greater isometric strength, muscle power, and speed performance, but Fr wrestlers had greater flexibility. Given the significant effect sizes favoring GR wrestlers, it is possible that they focused on training strategies to improve physical strength-power performance. However, considering the significant effect size favoring Fr wrestlers, it is possible that they focused on training strategies to improve flexibility because Fr wrestling techniques require a larger range of motion during both attack and defense.

Exercise in the cold causes greater irisin release but may not be enough for adropin.

When irisin and adropin were discovered, it was popularly hoped that they would become therapies for metabolic disorders that threaten global health. However, contradictory results have been reported in the subsequent period. Irisin, induced by exercise or cold exposure, is believed to be a myokine that causes the browning of adipose tissue thus increasing energy expenditure. Adropin is thought to be beneficial for health by regulating blood flow, capillary density, and playing an active role in glucose and insulin homeostasis. However, there were no experimental studies investigating the simultaneous effect of exercise and cold exposure in humans. The purpose of this study was to investigate irisin and adropin responses in young healthy individuals performing aerobic exercise in different environmental temperatures. Twenty-seven young, healthy individuals participated in this study. Participants performed 40 min of aerobic running exercise in environmental temperatures of 0°C, 12°C, and 24°C. Venous blood samples were taken pre- and post-exercise. Irisin and adropin levels were analyzed using an enzyme-linked immunosorbent assay. The principal findings showed that while serum irisin concentrations significantly increased after aerobic exercise was performed at an environmental temperature of 0°C, there was no significant difference between pre- and post-exercise recordings for physical activity performed at 12°C and 24°C. Adropin concentrations, however, remained unchanged between pre- and post-exercise at 0°C, 12°C, and 24°C. Interestingly, the exercise at 0°C caused an increase in adropin (12.5%), but this amount was not enough to be a statistically significant result. The findings of this study suggest that aerobic exercise in a cold environment causes greater irisin release. However, the combined effect of exercise and cold exposure may not be enough to statistically increase adropin level.

Effects of sprint distance and repetition number on energy system contributions in soccer players.

BACKGROUND/OBJECTIVE: This study aims to compare the effect of sprint distance and repetition number on performance, physiological responses, and energy systems contributions. METHODS: Eighteen male university league soccer players (age: 19.9 ± 1.6 years, height: 177.9 ± 4.7 cm, body mass: 72.4 ± 6.3 kg, percentage body fat: 8.9 ± 1.8, training experience: 7.4 ± 1.6 years) completed two different repeated sprint protocols: 20 × 20 m (20 × 20) and 10 × 40 m (10 × 40) with 15s and 30s rest intervals, respectively. Oxygen uptake (VO2) were measured during the rest, exercise, and recovery phases. Rest and peak blood lactate concentrations were determined. Using VO2 and lactate values, the energy system contributions were calculated using a mono-exponential model and mathematical calculations. Energy systems contributions and total energy expenditure (TEE) were calculated both for the entire protocol (overall) and for the sprints only. RESULTS: Ratings of perceived exertion (RPE), peak and mean heart rate (HR) responses were significantly higher in the 20 × 20 whereas lactate response was higher in the 10 × 40. TEE was similar between the 10 × 40 (586.3 ± 60.8 kJ) and 20 × 20 (595.6 ± 57.5 kJ). For overall estimations, the 10 × 40 and 20 × 20 presented similar results of oxidative (47.5 ± 5.4 vs 45.7 ± 5.1 kJ min-1) and phosphagen (44.7 ± 5.4 vs (42.9 ± 4.8 kJ min-1) systems contributions whereas glycolytic contribution was higher in the 10 × 40 (15.5 ± 2.2 vs 12.8 ± 2.3 kJ min-1). For sprints only estimation, the phosphagen (257.6 ± 31.5 vs 225.2 ± 28.2 kJ min-1), glycolytic (89.4 ± 13.4 vs 67.3 ± 12.5 kJ min-1), and oxidative (76.9 ± 6.9 vs 72.0 ± 7.9 2 kJ min-1) systems contributions were higher in the 10 × 40. CONCLUSIONS: Although HR and RPE responses were higher in the 20 × 20, phosphagen (during sprints) and glycolytic (during both sprints and overall protocol) were higher in the 10 × 40 protocol. Therefore, the 10 × 40 protocol seems more reasonable for developing or evaluating the anaerobic systems.

Acute and chronic effects of aerobic exercise on serum irisin, adropin, and cholesterol levels in the winter season: Indoor training versus outdoor training.

The aim of this study is to investigate the acute and chronic effects of aerobic training performed indoors and outdoors on irisin, adropin, and cholesterol levels in winter. Thirty-two healthy males participated in this study. Participants were divided into two groups: outdoor group (n = 16) and indoor group (n = 16). They then performed 40-min aerobic running exercises 4 days/week for 18 weeks. The outdoor group trained at -5°C-5°C environmental temperature, while the indoor group trained at 21°C-25°C. Blood samples were collected before and after the 18-week training period and immediately after the first training. The results showed that single aerobic exercise induced minimal increase in serum irisin concentrations in both groups. In addition, irisin levels did not change in the outdoor group but significantly decreased in the indoor group after the 18-week training period. Aerobic exercise had no acute or chronic effects on serum adropin levels in the indoor group. However, the aerobic training caused a decrease in adropin levels chronically, but there was no acute effect after single aerobic exercise in the outdoor group. Furthermore, there was no acute effect on high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and total cholesterol after single aerobic exercise in both groups. However, after the 18-week training period, there was a significant increase in HDL-C levels in both groups. Moreover, the increase in HDL-C in the outdoor group was higher than in the indoor group. Thus, this study provides evidence for the beneficial chronic effects of aerobic exercise and cold on HDL-C levels as well as the beneficial acute effects on irisin concentrations.