Associations between the occurrence of the ACTN3 R577X, ACE I/D, BDKRB2 +9/-9 polymorphisms and anaerobic performance among a group of elite fencers

Introduction: This research aims to detect possible associations between the ACTN3 R577X, ACE I/D, BDKRB2 +9/-9 genetic polymorphisms, and selected anaerobic performance indicators among elite and sub-elite fencers. Methods: The sample of participants included a group of 20 fencers (males, age 25.5 ± 6.9 years; height 185.1 ± 5.8; weight 78.3 ± 9.8). We obtained genotype analysis for selected polymorphisms (ACTN3 R577X, ACE I/D, BDKRB2 +9/-9) through buccal swabs. 30-second Wingate test was used for the anaerobic performance where the following variables were monitored: the maximal anaerobic performance – Pmax [W], the anaerobic capacity – AnC [kJ], the total number of revolutions – TR [n], the peak blood lactate concentration – LApeak [mmol·l-1]. Results: Within ACTN3 R577X polymorphism, no differences were found in the observed variables between genotypes. However, ACE I/D heterozygotes reached higher Pmax, AnC, and LApeak values than homozygotes. Furthermore, BDKRB2 +9/-9 polymorphism homozygotes with -9 allele reached higher Pmax and AnC values than homozygotes with +9 allele. No statistical differences were found in all monitored variables between genotypes of monitored polymorphisms. Conclusions: The research findings might serve as another useful piece of knowledge related to the existing statements in the field of genetics, focusing on speed-strength performance problems. It should be highlighted that current studies are only the first steps in helping us better understand the associations between genetic factors and performance in sports.

Effects of surgical and FFP2/N95 face masks on cardiopulmonary exercise capacity

Background Due to the SARS-CoV2 pandemic, medical face masks are widely recommended for a large number of individuals and long durations. The effect of wearing a surgical and a FFP2/N95 face mask on cardiopulmonary exercise capacity has not been systematically reported. Methods This prospective cross-over study quantitated the effects of wearing no mask (nm), a surgical mask (sm) and a FFP2/N95 mask (ffpm) in 12 healthy males (age 38.1 ± 6.2 years, BMI 24.5 ± 2.0 kg/m2). The 36 tests were performed in randomized order. The cardiopulmonary and metabolic responses were monitored by ergo-spirometry and impedance cardiography. Ten domains of comfort/discomfort of wearing a mask were assessed by questionnaire. Results The pulmonary function parameters were significantly lower with mask (forced expiratory volume: 5.6 ± 1.0 vs 5.3 ± 0.8 vs 6.1 ± 1.0 l/s with sm, ffpm and nm, respectively; p = 0.001; peak expiratory flow: 8.7 ± 1.4 vs 7.5 ± 1.1 vs 9.7 ± 1.6 l/s; p < 0.001). The maximum power was 269 ± 45, 263 ± 42 and 277 ± 46 W with sm, ffpm and nm, respectively; p = 0.002; the ventilation was significantly reduced with both face masks (131 ± 28 vs 114 ± 23 vs 99 ± 19 l/m; p < 0.001). Peak blood lactate response was reduced with mask. Cardiac output was similar with and without mask. Participants reported consistent and marked discomfort wearing the masks, especially ffpm. Conclusion Ventilation, cardiopulmonary exercise capacity and comfort are reduced by surgical masks and highly impaired by FFP2/N95 face masks in healthy individuals. These data are important for recommendations on wearing face masks at work or during physical exercise.

Energetic and Biomechanical Contributions for Longitudinal Performance in Master Swimmers

Background: The current study aimed to verify the changes in performance, physiological and biomechanical variables throughout a season in master swimmers. Methods: Twenty-three master swimmers (34.9 ± 7.4 years) were assessed three times during a season (December: M1, March: M2, June: M3), in indoor 25 m swimming pools. An incremental 5 × 200 m test was used to evaluate the speed at 4 mmol·L−1 of blood lactate concentration (sLT), maximal oxygen uptake (VO2max), peak blood lactate ([La-]peak) after the test, stroke frequency (SF), stroke length (SL), stroke index (SI) and propelling efficiency (ηp). The performance was assessed in the 200 m front crawl during competition. Results: Swimming performance improved between M1, M2 (2%, p = 0.03), and M3 (4%, p < 0.001). Both sLT and VO2max increased throughout the season (4% and 18%, p < 0.001, respectively) but not [La-]peak. While SF decreased 5%, SL, SI and ηp increased 5%, 7%, and 6% (p < 0.001) from M1 to M3. Conclusions: Master swimmers improved significantly in their 200 m front crawl performance over a season, with decreased SF, and increased SL, ηp and SI. Despite the improvement in energetic variables, the change in performance seemed to be more dependent on technical than energetic factors.

Peak Blood Lactate Concentration and Its Arrival Time Following Different Track Running Events in Under-20 Male Track Athletes

Purpose: To determine (1) the time of arrival of peak blood lactate concentration ([BLa]peak) followed by various track events and (2) significant correlation, if any, between average velocity and [BLa]peak in these events. Methods: In 58 under-20 male track athletes, heart rate was recorded continuously and blood lactate concentration was determined at various intervals following 100-m (n = 9), 200-m (n = 8), 400-m (flat) (n = 9), 400-m hurdles (n = 8), 800-m (n = 9), 1500-m (n = 8), 3000-m steeplechase (n = 7), and 5000-m (n = 10) runs. Results: The [BLa]peak, in mmol/L, was recorded highest following the 400-m run (18.27 [3.65]) followed by 400-m hurdles (16.25 [3.14]), 800-m (15.53 [3.25]), 1500-m (14.71 [3.00]), 200-m (14.42 [3.40]), 3000-m steeplechase (11.87 [1.48]), 100-m (11.05 [2.36]), and 5000-m runs (8.65 [1.60]). The average velocity of only the 400-m run was found to be significantly correlated (r = .877, p < 0.05) with [BLa]peak. The arrival time of [BLa]peak following 100-m, 200-m, 400-m, 400-m hurdles, 800-m, 1500-m, 3000-m steeplechase, and 5000-m runs was 4.44 (0.83), 4.13 (0.93), 4.22 (0.63), 3.75 (0.83), 3.34 (1.20), 2.06 (1.21), 1.71 (1.44), and 1.06 (1.04) minutes, respectively, of the recovery period. Conclusion: In under-20 runners, (1) [BLa]peak is highest after the 400-m run, (2) the time of appearance of [BLa]peak varies from one event to another but arrives later after sprint events than longer distances, and (3) the 400-m (flat) run is the only event wherein the performance is significantly correlated with the [BLa]peak.

Do Performance Parameters Compare Between an Anaerobic Set and the 100-M Event in Swimming?

AIM: Anaerobic interval sets are commonly used in the training program of swimmers competing in short-distance events. However, data regarding the way that these sets compare to the competitive events are lacking. The aim of this study was to examine if there are differences in speed, blood lactate, stroke rate (SR), and stroke index (SI) between an anaerobic set of 4 × 50 m maximal swimming with work-to-rest ratio of approximately 1:4 and the 100-m event in freestyle stroke. MATERIAL & METHOD: Twenty-seven competitive swimmers (11 males, 16 females), aged 16.1 ± 1.1 years, completed the two tests on different days, in a random counterbalanced order. In each test, blood lactate was measured before and repeatedly after exercise through a portable lactate analyzer. Time and SR were recorded for each 50 m of the tests, and speed and SI were subsequently calculated. Three-way analysis of variance (time × test × gender) and Pearson’s correlation analysis were used. The level of statistical significance was set at α = 0.05. RESULTS: Average speed was higher at 4 × 50 m compared to 100 m (1.62 ± 0.10 and 1.56 ± 0.10, respectively, p < 0.001) and was correlated between tests (r = 0.930, p < 0.001). Peak blood lactate after 4 × 50 m was higher compared to 100 m (14.8 ± 3.1 and 10.9 ± 3.3 mmol/L, respectively, p < 0.001) and was correlated between tests (r = 0.640, p < 0.001). Average SR was higher in 4 × 50 m compared to 100 m (47.0 ± 3.6 and 44.5 ± 3.2 cycles/min, respectively, p < 0.001) and was correlated between tests (r = 0.836, p < 0.001). Average SI did not differ but was correlated between tests (r = 0.937, p < 0.001). Males had higher SR and SI and were faster than females (p < 0.05) but did not differ from females regarding lactate. CONCLUSIONS: Based on the aforementioned differences and correlations, the 4 × 50 m training set could be used to improve the parameters that have impact on performance in the 100-m event.

The Effect of a Combat Swimming Training Program on Swimming Performance

Aim: To explore the effect of a combat swimming training program (CSTP), with and without equipment, on swimming performance. Material & Method: 45 male army officer cadets volunteered to participate in the study and were randomly divided into three groups: a control group (CG) and two experimental groups. The experimental groups participated in a 4-week combat swimming training program with equipment (CSTPE) or without equipment (CSTPS). Prior to and after the CSTP, all groups performed a 400-m and a 4 × 50-m swimming task, and the time to complete the task, peak blood lactate, and peak heart rate were measured. Results: The time to complete the 400-m and 4 × 50-m trials improved significantly only in the CSTPE group (490 ± 66 s pre and 463 ± 50 s post for 400 m; and 205 ± 28 s pre and 192 ± 19 s post for 4 × 50 m; p < 0.05), while the CG and CTSPS groups did not improve their time significantly in either trial. All groups presented similar peak lactate and peak heart rate values. Conclusions: The results suggest that only the CSTPE group improved swimming performance in both the 400-m and 4 × 50-m trials.

Physical and Physiological Demands of Recreational Team Handball for Adult Untrained Men

Lack of motivation to exercise was reported as a major cause of sedentary behavior in adulthood. This descriptive study examines the acute physical and physiological demands of recreational team handball and evaluates whether it could be suggested as an exercise mode for fitness and health enhancement in 33–55-year-old untrained men. Time-motion, heart rate (HR), and blood lactate analyses were obtained from 4 recreational matches. Mean distance covered during the 60 min matches was6012±428 m. The players changed match activity386±70times, of which high-intensity runs and unorthodox movements amounted to59±18and26±26per match, respectively. The most frequent highly demanding playing actions were jumps and throws. Match average and peak HR were82±6% and93±5% HRmax, respectively. Players exercised at intensities between 81 and 90% HRmaxfor 47% (28±14 min) and >90% HRmaxfor 24% (14±15 min) of total match time. Match average and peak blood lactate values were3.6±1.3and4.2±1.2 mM, respectively. Recreational team handball is an intermittent high-intensity exercise mode with physical and physiological demands in the range of those found to have a positive effect on aerobic, anaerobic, and musculoskeletal fitness in adult individuals. Training studies considering recreational team handball as a health enhancing intervention are warranted.

The Sensitivity of Differential Ratings of Perceived Exertion as Measures of Internal Load

Purpose:To investigate the sensitivity of differential ratings of perceived exertion (dRPE) as measures of internal load.Methods:Twenty-two male university soccer players performed 2 maximal incremental-exercise protocols (cycle, treadmill) on separate days. Maximal oxygen uptake (V̇O2max), maximal heart rate (HRmax), peak blood lactate concentration (B[La]peak), and the preprotocol-to-postprotocol change in countermovement-jump height (ΔCMJH) were measured for each protocol. Players provided dRPE (CR100) for breathlessness (RPE-B) and leg-muscle exertion (RPE-L) immediately on exercise termination (RPE-B0, RPE-L0) and 30 min postexercise (RPE-B30, RPE-L30). Data were analyzed using magnitude-based inferences.Results:There were clear between-protocols differences for V̇O2max (cycle 46.5 ± 6.3 vs treadmill 51.0 ± 5.1 mL · kg−1 · min−1, mean difference –9.2%; ±90% confidence limits 3.7%), HRmax (184.7 ± 12.7 vs 196.7 ± 7.8 beats/min, –6.0%; ±1.7%), B[La]peak (9.7 ± 2.1 vs 8.5 ± 2.0 mmol/L, 15%; ±10%), and ΔCMJH (–7.1 ± 4.2 vs 0.6 ± 3.6 cm, –23.2%; ±5.4%). Clear between-protocols differences were recorded for RPE-B0 (78.0 ± 11.7 vs 94.7 ± 9.5 AU, –18.1%; ±4.5%), RPE-L0 (92.6 ± 9.7 vs 81.3 ± 14.1 AU, 15.3%; ±7.6%), RPE-B30 (70 ± 11 vs 82 ± 13 AU, –13.8%; ±7.3%), and RPE-L30 (86 ± 12 vs 65 ± 19 AU, 37%; ±17%). A substantial timing effect was observed for dRPE, with moderate to large reductions in all scores 30 min postexercise compared with scores collected on exercise termination.Conclusion:dRPE enhance the precision of internal-load measurement and therefore represent a worthwhile addition to training-load-monitoring procedures.

The kinetics of blood lactate in boys during and following a single and repeated all-out sprints of cycling are different than in men

This study characterized the impact of high-intensity interval training on the kinetics of blood lactate and performance in trained boys and men. Twenty-one boys (11.4 ± 0.8 years) and 19 men (29.4 ± 5.0 years) performed a set of four 30-s sprints with 2-min of rest and a single 30-s sprint on 2 separate occasions (randomized order) with assessment of performance. Blood lactate was assayed after each sprint and during 30 min of recovery from both tests. The individual time-curves of blood lactate concentration were fitted to the biexponential function as follows: [Formula: see text], where the velocity parameters γ1and γ2reflect the capacity to release lactate from the previously active muscle into the blood and to subsequently eliminate lactate from the organism, respectively. In both tests, peak blood lactate concentration was significantly lower in the boys (four 30-s sprints: 12.2 ± 3.6 mmol·L−1; single 30-s sprint: 8.7 ± 1.8 mmol·L−1) than men (four 30-s sprints: 16.1 ± 3.3 mmol·L−1; single 30-s sprint: 11.5 ± 2.1; p < 0.001). The boys exhibited faster γ1(1.4531 ± 0.65 min; p < 0.001) and γ2(0.059 ± 0.023 min; p = 0.01) in the single 30-s sprint and faster γ2(0.049 ± 0.016 min; p = 0.01) in the four 30-s sprints. The worsening of performance from the first to the last of the four 30-s sprints was less pronounced in boys (9.2% ± 13.9%) than men (19.2% ± 11.5%; p = 0.01). In the present study boys, when compared with men, exhibited lower Peak blood lactate concentration; less pronounced decline in performance during the sprints concomitantly with more rapid release and elimination during the single 30-s sprint; and faster elimination of lactate following the four 30-s sprints.