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Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study validated muscle activation estimations generated by OpenSim during the gait of elderly fallers. Ten healthy elderly participants walked on an instrumented treadmill, monitored by motion capture, force platforms, and 12 surface EMG sensors. Static optimization was used to calculate muscle activations, evaluated through cosine similarity, comparing them with EMG signals from 12 muscles of the right leg. Findings revealed varied similarity levels across muscles and gait phases. During stance phase, tibialis anterior (TIBA), peroneus longus (PERL), soleus (SOL), gastrocnemius lateralis (GASL), semitendinosus (SEMI), tensor fasciae latae (TFL), and rectus femoris (RECF) demonstrated poor similarity (cosim < 0.6), while gluteus medius (GMED), biceps femoris long head (BFLH), and vastus lateralis (VL) exhibited moderate similarity (0.6 ≤ cosim ≤ 0.8), and gluteus maximus (GMAX) and vastus medialis (VASM) displayed high similarity (cosim > 0.8). During the swing phase, only SOL demonstrated inadequate similarity, while GASL, GMAX, GMED, BFLH, SEMI, TFL, RECF, and VASL exhibited moderate similarity, and TIBA, PERL, and VASM showed high similarity. Comparing the different 10% intervals of the gait cycle generally produced more favorable similarity results. For most of the muscles and intervals, good agreement was found. Moderate agreement was estimated in the cases of TIBA (0–10%), PERL (60–70%), GASL (60–70%), TFL (10–20%), RECF (0–10%, 80–100%), and GMED (50–60%). Bad agreement was found in the cases of SOL (60–70%), GASL (0–10%), and TFL (0–10%). In conclusion, the study's validation outcomes were acceptable in most cases, underlining the potential for user-friendly musculoskeletal modeling routines to study muscle output during elderly gait. [ABSTRACT FROM AUTHOR]

Myrkos, A, Smilios, I, Zafeiridis, A, Iliopoulos, S, Kokkinou, EM, Douda, H, and Tokmakidis, SP. Effects of work and recovery duration and their ratio on cardiorespiratory and metabolic responses during aerobic interval exercise. J Strength Cond Res 36(8): 2169–2175, 2022—This study examined the effect of work and recovery durations and of work-to-rest ratio (WRR) on total exercise time and oxygen consumption (V̇ o 2max), on exercise time above 80, 90, and 95% of V̇ o 2max and HRmax, and on blood lactate concentrations during aerobic interval exercise. Twelve men (22.1 ± 1 year) executed, until exhaustion, 4 interval protocols at an intensity corresponding to 100% of maximal aerobic velocity. Two protocols were performed with work bout duration of 120 seconds and recovery durations of 120 (WRR: 1:1) or 60 seconds (WRR: 2:1), and 2 protocols with work bout duration of 60 seconds and recovery durations of 60 (WRR: 1:1) or 30 seconds (WRR: 2:1). When compared at equal exercise time, total V̇ o 2 and exercise time at V̇ o 2 above 80, 90, and 95% of V̇ o 2max were longer (p < 0.05) in 120:120, 120:60 and 60:30 vs. the 60:60 protocol. When analyzed for total exercise time (until exhaustion), total V̇ o 2 was higher (p < 0.01) in the 60:60 compared with all other protocols, and in the 120:120 compared with 120:60. Exercise time >95% of V̇ o 2max and HRmax was higher (p < 0.05) in the 120:120 vs. the 60:60 protocol; there were no differences among protocols for exercise time >90% of V̇ o 2max and HRmax. Blood lactate was lower (p < 0.05) in the 60:60 compared with all other protocols and in the 60:30 vs. the 120:60. In conclusion, when interval exercise protocols are executed at similar effort (until exhaustion), work and recovery durations do not, in general, affect exercise time at high oxygen consumption and HR rates. However, as work duration decreases, a higher work-to-recovery ratio (e.g., 2:1) should be used to achieve and maintain high (>95% of maximum) cardiorespiratory stimulus. Longer work bouts and higher work-to-recovery ratio seem to activate anaerobic glycolysis to a greater extent, as suggested by greater blood lactate concentrations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the anaerobic power of elite male volleyball players, using the Wingate Anaerobic Test to examine the relationship between anaerobic power and jumping performance. Athletes (n = 56) and Nonathletes (n = 53) were divided into three age groups: Adults (18-25 yr.), Juniors (15-16 yr.), and Youth (10-11 yr.). Measurements of height, body mass, vertical jump and Wingate scores indicated higher values for athletes. The specific training effects of anaerobic power were more pronounced at the age of 10-11 years than for Nonathletes. A significant correlation coefficient between peak power and vertical jump was found for Athletes (r = .86) and for the total group (r = .82). These results indicated that vertical jump may predict the maximal anaerobic power and could be used by coaches as a practical and easy-to-apply field screening test for evaluation in volley ball training.

The purpose of this study was to examine the effects of ibuprofen on delayed onset muscle soreness (DOMS), indirect markers of muscle damage and muscular performance. Nineteen subjects (their mean [+ or -] SD] age, height, and weight was 24.6 [+ or -] 3.9 years, 176.2 [+ or -] 11.1 cm, 77.3 [+ or -] 18.7 kg) performed the eccentric leg curl exercise to induce muscle soreness in the hamstrings. Nine subjects took an ibuprofen pill of 400 mg every 8 hours within a period of 48 hours, whereas 10 subjects received a placebo randomly (double blind). White blood cells (WBCs) and creatine kinase (CK) were measured at pre-exercise, 4-6, 24, and 48 hours after exercise and maximal strength (1 repetition maximum). Vertical jump performance and knee flexion range of motion (ROM) were measured at pre-exercise, 24 and 48 hours after exercise. Muscle soreness increased (p < 0.05) in both groups after 24 and 48 hours, although the ibuprofen group yielded a significantly lower value (p < 0.05) after 24 hours. The WBC levels were significantly (p < 0.05) increased 4-6 hours postexercise in both groups with no significant difference (p > 0.05) between the 2 groups. The CK values increased (p < 0.05) in the placebo group at 24 and 48 hours postexercise, whereas no significant differences (p > 0.05) were observed in the ibuprofen group. The CK values of the ibuprofen group were lower (p < 0.05) after 48 hours compared with the placebo group. Maximal strength, vertical jump performance, and knee ROM decreased significantly (p < 0.05) after exercise and at 24 and 48 hours postexercise in both the placebo and the ibuprofen groups with no differences being observed (p > 0.05) between the 2 groups. The results of this study reveal that intake of ibuprofen can decrease muscle soreness induced after eccentric exercise but cannot assist in restoring muscle function. Key Words: anti-inflammatory drugs, squat jump, counter movement jump, maximal concentric strength

The purpose of this study was to examine the test-retest reliability of the Eurofit motor fitness tests performed by university students. A total of 98 undergraduate students who were enrolled in physical education departments in Greece participated (29 men aged 19.5 [+ or -] 2.7 hr. and 66 women aged 19.4 [+ or -] 2.7 yr.). All Eurofit motor fitness tests and anthropometric measurements were obtained twice with one week between the two measurements. Intraclass correlation coefficient indicated satisfactory coefficients above .70 for most tests. The only exception was the plate-tapping test, which yielded a low value (R = .57). Further, the majority of the Eurofit test battery fitted well within the 95% confidence interval, and only three Eurofit motor fitness test items (flamingo balance, plate tapping, and sit-ups) presented a confidence limit below the value of .70. These findings indicated that the Eurofit test battery yielded reliable data for undergraduate students. However, modifications should be considered to improve the reliability of certain test items, for application to undergraduates.

This five-year follow-up nonrandomized controlled study evaluated community-based training and detraining on body composition and functional ability in older women. Forty-two volunteers (64.3 ± 5.1 years) were divided into four groups: aerobic training, strength training, combined aerobic and strength, and control. Body composition and physical fitness were measured at baseline, after nine months of training and after three months of detraining every year. After five years of training, body fat decreased, and fat free mass, strength, and chair test performance increased (p < .05) in all training groups. Training-induced favorable adaptations were reversed during detraining but, eventually, training groups presented better values than the control group even after detraining. Thus, nine months of annual training, during a five-year period, induced favorable adaptations on body composition, muscular strength, and functional ability in older women. Three months of detraining, however, changed the favorable adaptations and underlined the need for uninterrupted exercise throughout life. [ABSTRACT FROM AUTHOR]

Purpose: This study examined the effect of rest interval after the execution of a jump-squat set with varied external mechanical-power outputs on repeated-jump (RJ) height, mechanical power, and electromyographic (EMG) activity. Methods: Twelve male volleyball players executed 6 RJs before and 1, 3, 5, 7, and 10 min after the execution of 6 repetitions of jump squats with a load: maximized mechanical-power output (Pmax), 70% of Pmax, 130% of Pmax, and control, without extra load. Results: RJ height did not change (P = .44) after the jump squats, mechanical power was higher (P = .02) 5 min after the 130%Pmax protocol, and EMG activity was higher (P = .001) after all exercise protocols compared with control. Irrespective of the time point, however, when the highest RJ set for each individual was analyzed, height, mechanical power, and EMG activity were higher (P = .001-.04) after all loading protocols compared with control, with no differences observed (P = .53-.72) among loads. Conclusions: Rest duration for a contrast-training session should be individually determined regardless of the load and mechanical-power output used to activate the neuromuscular system. The load that maximizes external mechanical-power output compared with a heavier or a lighter load, using the jump-squat exercise, is not more effective for increasing jumping performance afterward. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of active and passive recovery of various durations after a 100-m swimming test performed at maximal effort. Methods: Eleven competitive swimmers (5 males, 6 females, age: 17.3 ± 0.6 y) completed two 100-m tests with a 15-min interval at a maximum swimming effort under three experimental conditions. The recovery between tests was 15 min passive (PAS), 5 min active, and 10 min passive (5ACT) or 10 min active and 5 min passive (10ACT). Self-selected active recovery started immediately after the first test, corresponding to 60 ± 5% of the 100-m time. Blood samples were taken at rest, 5, 10, and 15 min after the first as well as 5 min after the second 100-m test for blood lactate determination. Heart rate was also recorded during the corresponding periods. Results: Performance time of the first 100 m was not different between conditions (P > .05). The second 100-m test after the 5ACT (64.49 ± 3.85 s) condition was faster than 10ACT (65.49 ± 4.63 s) and PAS (65.89 ± 4.55 s) conditions (P < .05). Blood lactate during the 15-min recovery period between the 100-m efforts was lower in both active recovery conditions compared with passive recovery (P < .05). Heart rate was higher during the 5ACT and 10ACT conditions compared with PAS during the 15-min recovery period (P < .05). Conclusion: Five minutes of active recovery during a 15-min interval period is adequate to facilitate blood lactate removal and enhance performance in swimmers. Passive recovery and/or 10 min of active recovery is not recommended. [ABSTRACT FROM AUTHOR]

Purpose: To identify the physiological and anthropometric predictors of rhythmic gymnastics performance, which was defined from the total ranking score of each athlete in a national competition. Methods: Thirty-four rhythmic gymnasts were divided into 2 groups, elite (n = 15) and nonelite (n = 19), and they underwent a battery of anthropometric, physical fitness, and physiological measurements. The principal-components analysis extracted 6 components: anthropometric, flexibility, explosive strength, aerobic capacity, body dimensions, and anaerobic metabolism. These were used in a simultaneous multiple-regression procedure to determine which best explain the variance in rhythmic gymnastics performance. Results: Based on the principal-component analysis, the anthropometric component explained 45% of the total variance, flexibility 12.1%, explosive strength 9.2%, aerobic capacity 7.4%, body dimensions 6.8%, and anaerobic metabolism 4.6%. Components of anthropometric (r = .50) and aerobic capacity (r = .49) were significantly correlated with performance (P < .01). When the multipleregression model-y = 10.708 + (0.0005121 × VO2max) + (0.157 × arm span) + (0.814 × midthigh circumference) - (0.293 × body mass)-was applied to elite gymnasts, 92.5% of the variation was explained by VO2max (58.9%), arm span (12%), midthigh circumference (13.1%), and body mass (8.5%). Conclusion: Selected anthropometric characteristics, aerobic power, flexibility, and explosive strength are important determinants of successful performance. These findings might have practical implications for both training and talent identification in rhythmic gymnastics. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the acute changes in leukocyte number and cortisol after a single bout of soccer training. Methods: Ten elite female national-team soccer players and 8 nonathletes participated in the study. The duration of the exercise was 2 h, and it was performed at an intensity of 75% of maximal heart rate (HRmax). Blood samples were taken before, immediately after, and 4 h after a soccer training session to determine total white blood cells; the subsets of neutrophils, lymphocytes, monocytes, eosinophils, and basophils; and cortisol. At the same time, blood samples were obtained from nonathletes who refrained from exercise. Results: Data analysis indicated a significant increase in total white blood cells in the athletes postexercise (P < .001). The leukocytosis was still evident after 4 h of recovery (78% higher than the preexercise values), and there was a significant difference between athletes and nonathletes (P < .001). This leukocytosis was primarily caused by neutrophilia—there were no significant differences in lymphocytes after the end of exercise or between the 2 groups (P > 0.05). In addition, there was a statistically significant difference in cortisol concentration between athletes and nonathletes after the exercise (P < .001). Conclusion: These findings revealed that the single bout of soccer training at an intensity of 75% of HRmax induced leukocytosis without affecting the lymphocyte count in elite female athletes and probably the effectiveness of cellular components of adaptive immunity. Coaches should provide adequate time (>4 h) until the next exercise session. [ABSTRACT FROM AUTHOR]

A correction to the article "Aerobic adaptations following iso-effort training programs: An intense continuous and a high-intensity interval" that was published in the April 5, 2023 issue is presented.

Copyright of Science of Gymnastics Journal is the property of Science of Gymnastics Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Body size and dimensions, in conjunction with jumping ability, may constitute critical components for successful performance in Volleyball. The purpose of this study was: to measure a number of anthropometric characteristics and vertical jump performance of elite youth women volleyball players, from the national teams of the Balkan countries, and make comparisons based on nationality and players positions. The sample consisted of eighty six athletes (age: 15.5-18.5 years) from Greece (GR, n=21), Bulgaria (BU, n=20), Serbia (SER, n=11), Moldavia (MOL, n= 9), Turkey (TUR, n=12) and Romania (RO, n=13), distributed also as setters (n=14), outside hitters (n=31), universals (n=12), middle blockers (n=22) and liberos (n=7). The subjects were measured for body height, body mass, body mass index (BMI) and body fat percentage and performed four types of vertical jump; a squat jump initiated from a knee flexion of 90o, a counter-movement jump, a countermovement jump with arm swing and a drop jump from a dropping height of 40 cm from which reactive strength was also calculated. According to the results, GR and RO had higher body fat percentage than MOL and BU (p<.05). Middle blockers were taller than the setters, the outside hitters and the liberos (p<.01). Universals were taller than the setters and the liberos (p<.01) and the outside hitters than the liberos (p<.01). No differences were observed in BMI between the players and the teams (p>.05), though middle blockers had higher body mass than the setters, the outside hitters and the liberos (p<.05). In squat jump, counter movement jump and drop jump TUR had higher values than GR and BU (p<.05). In counter-movement jump with arm swing, TUR had also higher values than GR, BU and MOL (p<.05). Furthermore, TUR and SER had higher reactive strength values than GR and BU (p<.05) and TUR had also higher values than RO (p<.05). The evaluation of the physical characteristics and capacities provide the coaches useful information about the selection and development of young athletes as well as the effectiveness of the training programs. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to assess the validity of self-reported height and weight as a screen tool for estimating overweight and obesity in primary schoolchildren. Self-reported and measured height and body mass were derived from 181 boys and 197 girls (mean age 11.4±0.4 yrs). The BMI cutoff points adopted by the International Obesity Task Force were utilized to compare prevalence estimates of overweight and obesity obtained from self-reported and actual measures. The results revealed that the students tended to overestimate their height (+0.59±3.4 cm, p<.002) and underreport their body mass (-1.53±3.6 kg, p<.0005). Thus, self-reported BMI was approximately 0.79±1.8 kg.m-2 lower than measured BMI (p<.0005). The degree of self-report bias in weight, height, and BMI did not differ between genders. Overweight and obese participants showed greater bias in self-reported weight than normal/underweight participants. Based on self-reports, prevalence estimates were 24.6% for overweight and 3.7% for obesity, but measured data showed significantly higher rates (overweight: 28.3%, obesity: 9.5%, X2=277.66, p<.0005). The present findings imply that self-reported anthropometric data obtained from Greek primary schoolchildren might not be valid and could lead to erroneous estimating rates of childhood overweight and obesity. This is of major importance, given that many large-scale epidemiological studies are based on self-reported data. The high prevalence rates of overweight and obesity observed in our sample offer some support on the reported growing obesity prevalence in Greek children, underlining the need for continuous monitoring of excess adiposity problems in childhood, using valid and accurate health surveillance tools. [ABSTRACT FROM AUTHOR]

It is well recognized that exercise causes considerable changes in circulating leukocyte subpopulations. These changes appears to be related to exercise intensity and duration. Literature data shows immunosuppression in endurance athletes; however, team sports have received little attention with reference to acute effects of exercise on immune function. The aim of the present study was to investigate the acute changes in leukocyte number after a single bout of basketball training. Fifteen elite female basketball players, members of the national team and eight non-athletes participated in the study. The duration of the exercise was two hours and was performed at an intensity of 70% of maximal heart rate. Before the exercise (pre), immediately after (post) and four hours after the exercise conclusion (4 h) blood samples were taken in order to determine white blood cells and the subsets of neutrophils, lymphocytes, monocytes eosinophils and basophils. At the same time, blood samples were obtained from non-athletes. The analysis of data indicated significant increase in total white blood cells for the athletes (p<.001) after the end of exercise. The leukocytosis was still evident after four hours of recovery (25% higher from the pre-exercise values) and there was a significant difference between athletes and non-athletes (p<.001). This leukocytosis was primarily due to a neutrophilia as there were no significant differences in lymphocytes after the end of exercise and between the two groups (p>.05). These findings revealed that the single bout of basketball training induced a mild leukocytosis without affecting the lymphocyte count and the immune system in athletes. [ABSTRACT FROM AUTHOR]

The present study examined ratings of perceived exertion (RPE) in relation to physiological responses during an incremental exercise test in elite and non-elite rhythmic gymnasts in order to determine the proper training intensity. Thirty-nine gymnasts were divided into two groups (elite: n=15, non-elite: n=24) and performed an incremental exercise test on a cycle-ergometer up to exhaustion in order to determine RPE (scale 6-to-20), oxygen uptake, heart rate and lactate responses. Elite-athletes presented higher RPE and VO2max values at a maximal effort (p<0.001) while heart rate and lactate values between elite and non-elite gymnasts were similar. In addition, when examining the same relative exercise intensity, the RPE response was higher in elite-athletes than non-elite athletes and a significant correlation was obtained between RPE and athletic performance (r=0.83, p<0.01), based on total performance rank in national competitions. These results suggest that RPE appears to be an applicable measure of exercise intensity mostly in highly trained rhythmic gymnasts and may provide accurate information to coaches for better training regimes. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine whether parameters related to physical fitness and health are affected from curricular and extracurricular physical activity levels. A random sample of 155 Greek Primary School pupils (age 8.1±1.3 yr, height 132.8±9.3 cm, weight 30.9±8.2 kg) was subjected to anthropometric, motor (flexibility, standing broad jump, sit ups, agility-speed), and cardiovascular health-related (aerobic fitness, physical activity) fitness assessments, at the beginning of a school year and one year later. Physical activity levels were estimated with questionnaires. Subjects were subdivided into "athletes" (n=76) and "non-athletes" (n=79). "Athletes" were participating in organized extracurricular sport-activities, while "non-athletes" were involved only in school physical education (P.E.) classes. It was found that "athletes" had a better physical fitness and health profile and dedicated more time in high intensity activities (with a metabolic equivalent of >6 METs) than the "non-athletes". Furthermore, in both measurements a considerably higher percentage of children in the "non-athletes" group were classified as obese compared to the "athletes" group (22.7% vs. 10.5%, p<.03 and 27.8% vs. 7.9%, p<.001, respectively). It was concluded that (i) higher physical activity levels have a positive effect on selected health- and skill-related fitness parameters, and (ii) P.E. classes in Greek Primary Schools are not sufficient to bring about appropriate physiological adaptations and promote health. [ABSTRACT FROM AUTHOR]