Effects of combined strength and endurance training on exercise capacity in kidney transplant cyclists and runners.

INTRODUCTION: After transplantation, engaging in regular physical activity (PA) or sport is recommended for health. Participation to competitive sports is increasingly common among kidney transplant recipients while little is known on how training affects the physical performance in transplanted athletes. AIM: The purpose of this case study was to assess the effects of a tailored training program on exercise parameters in kidney transplant cyclists (CKTRs) and runners (RKTRs). METHODS: Twelve male transplanted athletes were enrolled. The workload at aerobic and anaerobic thresholds, the submaximal aerobic power (V'O2 stage) and rate of perceived exertion (RPE) during an incremental cycling or running test, and the peak instantaneous force (PIF) during a countermovement jump were assessed at baseline (T0) and after 6 months of tailored training (T6) consisting in strength and aerobic exercises. Exercise adherence, blood lipid profile and renal function were also investigated. RESULTS: Eight CKTRs and 4 RKTRs completed the 6-month training period, with a significant increase of training volume (minutes/week). The exercise adherence was met by 90% in both groups. At T6, there were significant (p<0.05) improvements of maximum workload attained, the workload corresponding to the aerobic threshold and PIF, while workloads at anaerobic threshold, V'O2 stage and RPE were unchanged. Blood cholesterol significantly decreased (p<0.01), while the other blood parameters were unchanged. CONCLUSIONS: These findings indicate that the combined strength and endurance training is well tolerated and may improve exercise performance in this selected population of KTRs.

The relationship between ambient temperature and match running performance of elite soccer players.

The influence of environmental factors on key physical parameters of soccer players during competitive match-play have been widely investigated in the literature, although little is known on the effects of sub-zero ambient temperatures on the performance of adult elite soccer players during competitive matches. The aim of this study was to assess how the teams' match running performance indicators are related to low ambient temperature during competitive matches in the Russian Premier League. A total of 1142 matches played during the 2016/2017 to 2020/2021 seasons were examined. Linear mixed models were used to assess the relationships between changes in ambient temperature at the start of the match and changes in selected team physical performance variables, including total, running (4.0 to 5.5 m/s), high-speed running (5.5 to 7.0 m/s) and sprint (> 7.0 m/s) distances covered. The total, running and high-speed running distances showed no significant differences across temperatures up to 10°C, while these showed small to large decreases at 11 to 20°C and especially in the >20°C ranges. On the contrary, sprint distance was significantly lower at temperature of -5°C or less compared to higher temperature ranges. At sub-zero temperatures, every 1°C lower reduced team sprint distance by 19.2 m (about 1.6%). The present findings show that a low ambient temperature is negatively related to physical match performance behavior of elite soccer players, notably associated with a reduced total sprint distance.

Impact of technical and physical performance on match outcome over five elite European soccer seasons.

BACKGROUND: The technical and physical performance, a key part of overall soccer performance, tend to evolve due to changes in game rules, playing styles, and training methodology. Nevertheless, little has been reported in the literature on how match performance has changed over time in elite championships and leagues. Thus, this study aimed to assess the impact of selected technical and physical team performance indicators on match outcome over five seasons in the Russian Premier League. METHODS: Twenty-two technical and physical team performance variables, recorded with an optical tracking system, were examined in 1186 matches played in the Russian Premier League during the 2016-2017 to 2020-2021 seasons. RESULTS: For pooled data in all examined seasons, shots on target were higher in won vs. drawn and lost matches. Percentage of challenges won was higher in won vs. drawn and lost matches. Sprint distance, counterattacks, shots, interceptions, recoveries, crosses, and the percentage of successful tackles all showed small though significant differences between match outcomes. Slightly greater odds of a more favorable match outcome were involved by increases in all selected variables, except crosses, showing an opposite effect. In the 2020-2021 season, ball possession time reported a slightly higher impact on match outcome than in previous seasons. CONCLUSIONS: The present results show that some technical performance variables have a great effect on match outcome, while other technical indicators and physical metrics have a smaller though still potentially relevant impact. These effects do not substantially differ across the five examined seasons.

Two vs. One Resistance Exercise Sessions in One Day: Acute Effects on Recovery and Performance.

Purpose: The purpose of this study was to compare the recovery response of one resistance training session (1TRS) vs. two resistance training sessions (2TRS) performed in 1 day, on upper body performance, muscle morphology and muscle soreness in trained men. Methods: Twenty-four resistance trained men were randomly assigned into a 1TRS group (N = 12; age = 25.0 ± 2.4 years; body mass = 87.6 ± 14.0 kg; height = 177.1 ± 4.9 cm) or into a 2TRS group (N = 10; age = 24.4 ± 1.6 years; body mass = 81.1 ± 5.6 kg; height = 176.6 ± 6.7 cm). 1TRS performed one training session involving eight sets of 10 reps at 70% of 1RM at the bench press, while 2TRS group divided the same training volume in two workouts, with a recovery time of 4 hr. Performance [bench press throw power (BTP) and isometric bench press (IBP)] and muscle thickness of pectoralis major (PECMT) were assessed at baseline (BL), 15-min, 24-hr and 48-hr post-exercise. Results: Training intensity was significantly higher in 2TRS compared to 1TRS (p < .001). Faster recovery rates were detected for BTP (p = .039) and PECMT (p = .05) in 2TRS compared to 1TRS. Both BTP and PECMT were significantly more affected (p < .05) in 1TRS than in 2TRS at 24 h. Conclusions: Results indicate that the recovery process may be accelerated by splitting a high resistance training volume into two different training sessions performed in 1 day.

The Physical Demands of Match-Play in Academy and Senior Soccer Players from the Scottish Premiership.

The present study aimed to assess the physical match performance among senior and youth soccer players from an elite Scottish Premiership club during the 2021/2022 season. Twenty-two first team (25.9 ± 4.5 years, 78.3 ± 8.2 kg, 1.82 ± 0.07 cm) and 16 youth players (16.8 ± 0.9 years, 70.1 ± 6.8 kg, 177 ± 5.8 cm) were examined. A selection of physical match performance variables were measured using a global positioning system. Linear mixed-effect regressions revealed for all examined variables no significant differences between first team and U-18 players and no significant differences between playing level by position interaction. Across both teams, Centre Backs compared to Wing Backs, showed a 295 m (p < 0.01) lower high-intensity distance, and performed on average 36 fewer very-high intensity decelerations (p = 0.03). Comparing to Wide Midfielders, Centre Backs showed lower total (1297 m, p = 0.01), high-intensity (350 m, p = 0.01), and sprint (167 m, p < 0.01) distances. Sprint distance was also lower in Centre Backs vs. Strikers (118 m, p = 0.03), and in Central Midfielders vs. both Strikers (104 m, p = 0.03) and Wide Midfielders (154 m, p = 0.01). The present findings highlight the physical match performance of elite Scottish players and provide useful information within the context of understanding how methods of physical development of youth soccer are implemented in different countries.

The Immunological and Hormonal Responses to Competitive Match-Play in Elite Soccer Players.

This study aimed to examine the salivary immunoglobulin A (s-IgA) and salivary cortisol (s-Cort) responses to competitive matches in elite male soccer players. Data were collected for 19 players (mean ± SD, age: 26 ± 4 years; weight: 80.5 ± 8.1 kg; height: 1.83 ± 0.07 m; body-fat 10.8 ± 0.7%) from a Russian Premier League team throughout a 6-week period during the 2021-2022 season. Physical match loads were measured through an optical tracking system. s-IgA and s-Cort were assessed one day before each match (MD - 1), 60-min before kick-off, 30-min post-match, and 48-h post-match (MD + 2). At 60-min before kick-off, s-IgA values were lower than at MD - 1 (90% CI difference 15.7-71.3 µg/mL). Additionally, compared to 60-min before kick-off, s-IgA was higher at 30-min post-match (90% CI difference 1.8-57.8 µg/mL) and at MD + 2 (90% CI difference 5.4-60.5 µg/mL). At 30-min post-match, s-Cort was higher than at 60-min before kick-off (90% CI difference 4.84-7.86 ng/mL), while on MD + 2 s-Cort was higher than at 60-min before kick-off (90% CI difference 0.76-3.72 ng/mL). Mixed model regressions revealed that longer playing time and total distance covered, and higher number of high-intensity accelerations, involved smaller s-IgA differences between 30-min post-match and 60-min before kick-off, and between 60-min before kick-off and MD + 2. Additionally, greater high-intensity and sprint distances, and a higher number of high-intensity and maximal accelerations, involved smaller s-Cort differences between 60-min before kick-off and MD + 2. In conclusion, the present results demonstrate that using salivary monitoring combined with match load may be a useful tool to monitor individual mucosal immunity and hormonal responses to match-play and the subsequent recovery periods in elite soccer players.

Relationships Between Muscle Architecture, Deadlift Performance, and Maximal Isometric Force Produced at the Midthigh and Midshin Pull in Resistance-Trained Individuals.

ABSTRACT: Bartolomei, S, Rovai, C, Lanzoni, IM, and di Michele, R. Relationships between muscle architecture, deadlift performance, and maximal isometric force produced at the midthigh and midshin pull in resistance-trained individuals. J Strength Cond Res 36(2): 299-303, 2022-The aim of this study was to investigate the relationships between muscle architecture, lower-body power, and maximal isometric force produced at midthigh pull (MTP), and at midshin pull (MSP). Twenty experienced resistance-trained men (age = 25.5 ± 3.2 years; body mass = 86.9 ± 12.4 kg; body height = 178.0 ± 5.3 cm) were tested for deadlift 1 repetition maximum (1RM), countermovement jump (CMJ), peak force (PF), and rate of force development (pRFD20) produced at isometric MTP and isometric MSP. Subjects were also assessed for architecture of vastus lateralis (VL). Physiological muscle thickness, pennation angle, and fascicle length (FL) were measured. Pearson's correlation coefficients were calculated to assess the relationships between variables. In addition, differences between MTP and MSP were assessed using paired-sample t-tests. A significant (p < 0.05) difference was detected on the correlation between deadlift 1RM and MSP (r = 0.78; p < 0.001) compared with MTP (r = 0.55; p = 0.012). Moderate correlations were observed between MSP PF and VLFL (r = 0.55; p = 0.011). Midshin pull pRFD20 was the only parameter significantly correlated with CMJ (r = 0.50; p = 0.048). Significantly higher PF and pRFD20 were recorded in MTP compared with MSP (p = 0.007 and p = 0.003, respectively). The present results show that force produced from the floor position may be more important than force produced from a position that mimics the second pull of the clean for deadlift and vertical jump performances. Coaches and scientific investigators should consider using MSP to assess isometric PF using a test correlated with both muscle architecture and dynamic performances.

Mud Pack With Menthol and Arnica Montana Accelerates Recovery Following a High-Volume Resistance Training Session for Lower Body in Trained Men.

ABSTRACT: Bartolomei, S, Nigro, F, D'Amico, A, Cortesi, M, and Di Michele, R. Mud pack with menthol and Arnica montana accelerates recovery following a high-volume resistance training session for lower body in trained men. J Strength Cond Res 36(7): 1909-1915, 2022-The aim of this study was to compare the effects of a mud pack, containing menthol and Arnica montana, on the recovery responses following a high-volume resistance protocol. Ten resistance-trained men (mean ± SD: age = 25.3 ± 6.1 years; body mass = 79.1 ± 10.6 kg; height = 178.9 ± 7.5 cm) performed a high-volume resistance workout for lower body squat and leg extension, (5 sets of 10 reps at 70% of one repetition maximum for both exercises). All the subject used mud (MUD) or a placebo (PL) in randomized counterbalanced crossover design. MUD or PL were applied 4 times: 3, 19, 27, and 45 hours after the workout, on the skin surface above the quadriceps muscle of both legs. Muscle performance (countermovement jump power [CMJP], isokinetic leg press at 75 cm·s-1 and 25 cm·s-1 [ISOK75 and ISOK25, respectively], isometric squat [ISQ]), and morphology (muscle thickness of vastus lateralis [VLMT]), were measured before exercise (baseline [BL]), and 15 minutes (15P), 24 hours (24P), and 48 hours (48P) postexercise. In addition, muscle soreness was assessed at the same time points using a visual analog scale (VAS). No significant interactions (p > 0.05) between the trials were detected for CMJP, ISOK75, ISQ, and VLMT. A significant interaction between trials was noted for ISOK25 (p = 0.022) and for VAS (p = 0.001). ISOK25 was significantly (p < 0.01) reduced from BL at 15P, 24P and 48P in PL, whereas changes were significant (p < 0.05) at 15P and 24P only in MUD. The present findings indicate that MUD may enhance the recovery rate of strength and reduce muscle soreness after high-volume exercise. Muscle morphology do not seem to be influenced by mud packs.

A Comparison between Male and Female Athletes in Relative Strength and Power Performances.

The aim of this study was to compare male vs. female athletes in strength and power performance relative to body mass (BM) and lean body mass (LBM) and to investigate the relationships between muscle architecture and strength in both genders. Sixteen men (age = 26.4 ± 5.0 years; body mass = 88.9 ± 16.6 kg; height = 177.6 ± 9.3 cm) and fourteen women (age = 25.1 ± 3.2 years; body mass = 58.1 ± 9.1 kg; height = 161.7 ± 4.8 cm) were tested for body composition and muscle thickness (MT) of vastus lateralis muscle (VT), pectoralis major (PEC), and trapezius (TRAP). In addition, participants were tested for lower body power at countermovement jump (CMJP) and upper-body power at bench press throw (BPT). Participants were also assessed for one repetition maximum (1RM) at bench press (1RMBP), deadlift (1RMDE), and squat (1RMSQ). Significantly greater (p < 0.01) MT of the VL, PEC and TRAP muscles and LBM were detected in men compared to women. Significantly greater (p < 0.05) 1RMBP and BPT adjusted for LBM were detected in men than in women. No significant gender differences after adjusting for LBM were detected for 1RMSQ (p = 0.945); 1RMDE (p = 0.472) and CMJP (p = 0.656). Significantly greater (p < 0.05) results in all performance assessments adjusted for MT of the specific muscles, were detected in males compared to females. Superior performances adjusted for MT and LBM in men compared to women, may be related to gender differences in muscle morphology and LBM distribution, respectively.

Arm-Stroke Descriptor Variability during 200-m Front Crawl Swimming.

The present study aimed to explore the variability of the arm-stroke temporal descriptors between and within laps during middle-distance swimming event using IMMUs. Eight male swimmers performed a 200-m maximum front-crawl in which the inter-lap and intra-lap variability of velocity, stroke rate, stroke-phases duration and arm-coordination index were measured through five units of IMMU. An algorithm computes the 3D coordinates of the wrist by means the IMMU orientation and the kinematic chain of upper arm biomechanical model, and it recognizes the start events of the four arm-stroke phases. Velocity and stroke rate had a mean value of 1.47 ± 0.10 m·s-1 and 32.94 ± 4.84 cycles·min-1, respectively, and a significant decrease along the 200-m (p < 0.001; η2 = 0.80 and 0.47). The end of each lap showed significantly lower stroke rate compared to the start and the middle segment (p < 0.05; η2 = 0.55). No other significant inter-lap and intra-lap differences were detected. The two main findings are: (i) IMMUs technology can be an effective solution to continuously monitor the temporal descriptors during the swimming trial; (ii) swimmers are able to keep stable their temporal technique descriptors in a middle-distance event, despite the decrease of velocity and stroke rate.

Upper-Body Resistance Exercise Reduces Time to Recover After a High-Volume Bench Press Protocol in Resistance-Trained Men.

ABSTRACT: Bartolomei, S, Totti, V, Griggio, F, Malerba, C, Ciacci, S, Semprini, G, and Di Michele, R. Upper-body resistance exercise reduces time to recover after a high-volume bench press protocol in resistance-trained men. J Strength Cond Res 35(2S): S180-S187, 2021-The aim of this study was to compare the effects of active and passive strategies on the recovery response after a high-volume bench press protocol. Twenty-five resistance-trained men (mean ± SD: age = 25.8 ± 3.6 years; body mass = 87.1 ± 12.1 kg; and height = 177.4 ± 4.9 cm) performed a high-volume bench press session (8 sets of 10 reps at 70% of 1 repetition maximum). Subsequently, they were randomly assigned to an active recovery (AR) group (n = 11) or to a passive recovery (PR) group (n = 14). Active recovery consisted of light bench press sessions performed 6 hours and 30 hours after the high-volume exercise protocol. Muscle performance (bench throw power [BTP] and isometric bench press [IBP]) and morphology (muscle thickness of pectoralis major [PECMT] and of triceps brachii [TRMT]) were measured before exercise (baseline [BL]), and at 15-minute (15P), 24-hour (24P), and 48-hour (48P) post-exercise. Post-exercise recovery of both maximal strength and power was accelerated in AR compared with PR. Both BTP and IBP were significantly (p < 0.001) reduced at 15P and 24P in PR, whereas changes were significant (p < 0.001) at 15P only in AR. PECMT was still significantly (p = 0.015) altered from BL at 48P in PR, whereas changes were significant (p < 0.001) at 15P only in AR. No significant interactions (p > 0.05) between PR and AR were detected for TRMT and muscle soreness. The present results indicate that AR enhances the recovery rate after high-volume exercise sessions and may be included in resistance training programs to optimize muscle adaptations.

A Comparison Between Total Body and Split Routine Resistance Training Programs in Trained Men.

ABSTRACT: Bartolomei, S, Nigro, F, Malagoli Lanzoni, I, Masina, F, Di Michele, R, and Hoffman, JR. A comparison between total body and split routine resistance training programs in trained men. J Strength Cond Res 35(6): 1520-1526, 2021-The purpose of the present investigation was to compare the effects of total body (TB) versus split routine (SR) resistance training workouts on maximal strength and muscle hypertrophy in trained men. Twenty-one resistance-trained men were randomly assigned to either a TB (TB: age = 24.1 ± 4.4 years; body mass = 78.7 ± 11.3 kg; body height = 177.0 ± 3.9 cm) or the SR group (SR: age = 24.9 ± 4.2 years; body mass = 79.2 ± 9.5 kg; body height = 175.2 ± 6.0 cm). Both groups performed a 10-week resistance training program. Isokinetic bench press at 75 and 25 cm·s-1 (ISOK75 and ISOK25, respectively), isometric bench press (ISOBP), isometric squat (ISOSQ), and one repetition maximum BP and SQ assessments were performed before and after training. Muscle thickness of the pectoralis major (PECMT), superior part of trapezius (TRAPMT), and vastus lateralis (VLMT) muscles was also evaluated at the same timepoints using ultrasonography. Improvements were observed in both groups for all strength assessments and muscle thicknesses. Only changes in ISOK25 were significantly (p = 0.015) greater in TB than in SR, while significantly greater (p = 0.037) changes in VLMT were detected in SR compared with TB. Results indicated that a TB training paradigm may be more appropriate for maximal strength improvement, while an SR training protocol may be more optimal in stimulating muscle growth in experienced, resistance-trained men.

Lifetime Exposure to Recreational Swimming Training and its Effects on Autonomic Responses.

The aim of the present investigation was to assess the effect of long-term recreational swimming training on the cardiac autonomic responses in the healthy population. 70 habitual recreational swimmers (48.6±14.3 yrs.) and 60 sedentary adults (51.5±10.4 yrs.) were recruited. Arterial blood pressure was recorded with participants in supine position for 10 min, and the last 5 min were used to assess heart rate variability, baroreflex sensitivity, and hemodynamic analysis. The analysis of the questionnaire showed that the swimmers had practiced swimming for a mean of 14 years and 207 min/week. No difference was detected for body mass index between groups. Heart rate variability showed significant differences between groups both in the time and frequency domain analysis. We also found significant differences for baroreflex sensitivity. At rest, cardiac output and stroke volume were higher, whereas, heart rate, mean arterial pressure and total peripheral resistances were lower in the swimmers than in the sedentary subjects. Since heart rate variability measures are independent predictors of mortality, the present findings suggest that habitual recreational swimming may be protective against sudden cardiovascular events and, more in general, have a positive impact on cardiovascular health.

Effect of walking speed during gait in water of healthy elderly.

BACKGROUND: Walking in water (WW) is frequently used as an aquatic exercise in rehabilitation programs for the elderly. Understanding gait characteristics of WW is of primary importance to effectively design specific water-based rehabilitation programs. Moreover, as walking speed in water is reduced with a possible effect on gait parameters, the age- and environment-related changes during WW have to be investigated considering the effects of instantaneous walking speed. RESEARCH QUESTION: how do gait kinematic characteristics differ in healthy elderly between WW and on land walking condition (LW)? Do elderly show different walking patterns compared to young adults? Can these kinematic changes be accounted only by the different environment/age or are they also related to walking speed? METHODS: Nine healthy elderly participants (73.5 ±â€¯5.8 years) were acquired during walking in WW and LW at two different speeds. Kinematic parameters were assessed with waterproofed inertial magnetic sensors using a validated protocol. The influence of environment, age and walking speed on gait parameters was investigated with linear mixed models. RESULTS: Shorter stride distances and longer stride durations were observed in WW compared to LW. In the sagittal plane, hip and knee joint showed larger flexion in WW (>10deg over the whole stride and ∼28deg at foot strike, respectively). Furthermore, lower walking speeds and stride distances were observed in elderly compared to young adults. In the sagittal plane, a slightly more flexed hip joint and a less plantarflexed ankle joint (∼9 deg) were observed in the elderly. SIGNIFICANCE: The results showed the importance of assessing the walking speed during WW, as gait parameters can vary not only for the effect environment but also due to different walking speeds.

Training Load and Carbohydrate Periodization Practices of Elite Male Australian Football Players: Evidence of Fueling for the Work Required.

The authors aimed to quantify (a) the periodization of physical loading and daily carbohydrate (CHO) intake across an in-season weekly microcycle of Australian Football and (b) the quantity and source of CHO consumed during game play and training. Physical loading (via global positioning system technology) and daily CHO intake (via a combination of 24-hr recall, food diaries, and remote food photographic method) were assessed in 42 professional male players during two weekly microcycles comprising a home and away fixture. The players also reported the source and quantity of CHO consumed during all games (n = 22 games) and on the training session completed 4 days before each game (n = 22 sessions). The total distance was greater (p < .05) on game day (GD; 13 km) versus all training days. The total distance differed between training days, where GD-2 (8 km) was higher than GD-1, GD-3, and GD-4 (3.5, 0, and 7 km, respectively). The daily CHO intake was also different between training days, with reported intakes of 1.8, 1.4, 2.5, and 4.5 g/kg body mass on GD-4, GD-3, GD-2, and GD-1, respectively. The CHO intake was greater (p < .05) during games (59 ± 19 g) compared with training (1 ± 1 g), where in the former, 75% of the CHO consumed was from fluids as opposed to gels. Although the data suggest that Australian Football players practice elements of CHO periodization, the low absolute CHO intakes likely represent considerable underreporting in this population. Even when accounting for potential underreporting, the data also suggest Australian Football players underconsume CHO in relation to the physical demands of training and competition.

Longitudinal Analysis of Cardiovascular Risk Factors in Active and Sedentary Kidney Transplant Recipients.

Background: Despite the benefits of physical activity on cardiovascular risk in kidney transplant recipients (KTRs), the long-term effects of exercise have been poorly investigated. This is a three-year observational study comparing graft function and cardiovascular risk factors in active KTRs (AKTRs) vs. sedentary KTRs (SKTRs). Methods: KTRs with stable renal function were assigned to active or sedentary group in relation to the level of daily physical activity based on World Health Organization (WHO) recommendations (<150 or >150 minutes/week, respectively). Complete blood count, renal function indices, lipid profile, blood pressure and anthropometric measures were collected yearly for an observation period of three years. The comparisons between the two groups were performed by repeated measures analyses of covariance (ANCOVAs), with age as a covariate. Results: Fifty-four subjects were included in the study. Thirty of them were identified as AKTRs (M/F 26/4, aged 45 ± 12 years) and 24 as SKTRs (M/F 18/6, aged 51 ± 14 years). Baseline characteristics were similar between the groups except body mass index (BMI) that was significantly higher in SKTRs (p = 0.043). Furthermore, over the three-year observation period, BMI decreased in AKTRs and increased in SKTRs (p = 0.006). Graft function was stable in AKTRs, while it showed a decline over time in SKTRs, as indicated by the rise in serum creatinine levels (p = 0.006) and lower eGFR (p = 0.050). Proteinuria, glucose and uric acid levels displayed a decrease in AKTRs and an increase in SKTRs during the three-year period (p = 0.015, p = 0.004 and p = 0.013, respectively). Finally, concerning lipid profiles, AKTRs had a significant reduction over time of triglycerides levels, which conversely showed a clinically relevant increase in SKTRs (p = 0.014). Conclusions: Our findings indicate that regular weekly exercise training may counteract the increased cardiovascular risks and also prevent graft function decline in KTRs.

Passive Drag in Young Swimmers: Effects of Body Composition, Morphology and Gliding Position.

The passive drag (Dp) during swimming is affected by the swimmer's morphology, body density and body position. We evaluated the relative contribution of morphology, body composition, and body position adjustments in the prediction of a swimmer's Dp. This observational study examined a sample of 60 competitive swimmers (31 male and 29 female) with a mean (±SD) age of 15.4 ± 3.1 years. The swimmer's Dp was measured using an electro-mechanical towing device and the body composition was assessed using a bioelectrical impedance analyser. Body lengths and circumferences were measured in both the standing position and the simulated streamlined position. Partial correlation analysis with age as a control variable showed that Dp was largely correlated (p < 0.05) with body mass, biacromial- and bi-iliac-breadth, streamline chest circumference and breadth. Body mass, Body Mass Index, chest circumference and streamline chest circumference showed a significant and moderate to strong effect (η2 > 0.55) on Dp. Body mass was the best predictor of Dp explaining 69% of the variability. These results indicate that swimmers with lower Dp values were: (i) slimmer, with lower fat and fat-free mass, (ii) thinner, with lower shoulder breadth, chest circumference, and streamline trunk diameters (iii), shorter, with lower streamline height. These findings can be used for talent identification in swimming, with particular reference to the gliding performance.

Physical Condition, Glycemia, Liver Function, and Quality of Life in Liver Transplant Recipients After a 12-Month Supervised Exercise Program.

BACKGROUND AND AIMS: Despite the excellent long-term outcomes in liver transplant (LT) recipients, several medical complications related to lifestyle still represent an issue. This study examined the effects of a 12-month supervised aerobic and strength training program on the aerobic capacity, muscle strength, metabolic profile, liver function, and quality of life of a cohort of LT recipients. METHODS: LT recipients with stable liver function were assigned to interventional exercise (group A) or usual care (group B). Aerobic capacity, muscle strength, metabolic profile, liver and kidney function, and health-related quality of life were assessed at baseline and after 6 and 12 months. Group A attended supervised training sessions 3 times per week for 12 months. Group B received general recommendations about home-based exercise. RESULTS: Forty patients from 6 Italian LT centers were randomized. Twenty-nine (72.5%, men-to-women ratio 23:6, mean age, 52 ± 8 years) LT recipients completed the study. Baseline characteristics were similar between groups except for body mass index and time from LT. No episode of acute rejection nor increase of transaminases occurred. Maximum workload and body mass index increased in both groups over time, but fasting glucose significantly decreased in group A (94.0 ± 15.0 mg/dL vs 90.0 ± 17.0 mg/dL; P = .037) and increased in controls (95.0 ± 24.0 mg/dL vs 102.0 ± 34.0 mg/dL, P = .04). Upper limb muscle strength increased only in supervised LT recipients. Vitality and general and mental health domains significantly improved after physical exercise. CONCLUSIONS: Supervised combined training was safe and effective in increasing aerobic capacity, muscle strength, and quality of life and in improving glucose metabolism in stable LT recipients.

Effects of Intracyclic Velocity Variations on the Drag Exerted by Different Swimming Parachutes.

Cortesi, M, Di Michele, R, and Gatta, G. Effects of intracyclic velocity variations on the drag exerted by different swimming parachutes. J Strength Cond Res 33(2): 531-537, 2019-Swimming parachutes are often used as a tool for resisted swimming training. However, little is known on their behavior in terms of exerted drag as a consequence of intracyclic velocity fluctuations. This study aimed to assess the drag provided by 2 swimming parachutes of different shape, also characterized by different volumes and cross-sectional areas, under conditions of velocity variations in the range of those occurring in swimming. A flat square-shaped parachute (FLAT, cross-sectional area and volume: 400 cm; 0.12 L) and a truncated cone-shaped parachute (CONE, 380 cm; 7.15 L) were passively towed: (a) at constant velocities ranging from 1.0 to 2.2 m·s, and (b) with velocity fluctuations from 10 to 40% around a mean of 1.6 m·s. At constant velocities, FLAT showed 0.1 N (at 1.0 m·s) to 10.8 N (at 2.2 m·s) higher drag than CONE. For both parachutes, the average drag showed trivial differences between constant and any fluctuating velocity. Conversely, the maximum drag values were higher under conditions of velocity fluctuations than the respective values estimated under stationary instantaneous velocity, although this was observed in CONE only. These findings suggest that swimmers and coaches can select the parachute characteristics based on whether the focus is on increasing/decreasing the average drag or regulating the maximum resistance provided.

Physiological responses to partial-body cryotherapy performed during a concurrent strength and endurance session.

This investigation examined the effect of partial-body cryostimulation (PBC) performed in the recovery time between a strength training and an interval running (IR) session. Nine rugby players (age, 23.7 ± 3.6 years; body mass index, 28.0 ± 2.6 kg·m-2) were randomly exposed to 2 different conditions: (i) PBC: 3 min at -160 °C, and (ii) passive recovery at 21 °C. We performed the bioelectrical impedance analysis (BIA) and recorded temperature and cardiac autonomic variables at 3 time points: at baseline, after strength training, and after 90 min of recovery. In addition, blood lactate concentration was measured 1 min before and 2.5 min after the IR. Heart rate (HR), energy cost, minute ventilation, oxygen uptake, and metabolic power were assessed during the IR. Homeostatic hydration status was affected by the execution of an intense strength training subsession. Then, after PBC, the BIA vector was restored close to normohydration status. Autonomic variables changed over time in both conditions, although the mean differences and effect sizes were greater in the PBC condition. During IR, HR was 3.5% lower after PBC, and the same result was observed for oxygen uptake (∼4.9% lower) and ventilation (∼6.5% lower). The energy cost measured after cryotherapy was ∼9.0% lower than after passive recovery. Cryotherapy enhances recovery after a single strength training session, and during subsequent IR, it shows a reduction in cardiorespiratory and metabolic parameters. PBC may be useful for those athletes who compete or train more than once in the same day, to improve recovery between successive training sessions or competitions.