Aim: Although several tests have been used for monitoring neuromuscular function, their sensitivity to fatigue in athletes of team-based sports remains inconclusive. This study investigated the signal-to-noise ratio (SNR) of countermovement jump (CMJ), squat jump (SJ), sprint performance of 10 and 30 m (Sp-10 m; and Sp-30 m, respectively), and mechanical properties of sprints obtained through the MySprint app. Methods: Thirteen national rugby sevens players performed eight CMJ and SJ, and four sprint trials for baseline assessment, repeating all tests at 24-, 48-, and 72-h after a sport-specific fatigue protocol. Data analysis was performed using a linear multilevel modelling procedure through established Bayesian methods. Acceptable sensitivity was assumed for measures with SNR equal to or below -1. Results: The highest mean estimates of SNR at all moments were found in rate of force in 10 m (RF-10 m) (posterior mode: -2.15 to -2.33), followed by CMJ, SJ, Sp-30 m, maximal power output (Pmax), peak of rate of force (RFpeak), and theoretical and measured maximal horizontal velocity (V0, and Vmax), which showed similar mean values of SNR at 24-, 48-, and 72-h after exercise (posterior mode: -1.29 to -1.80). Conclusions: These results suggest that measures more specific to the task performed during the fatigue protocol showed higher sensitivity. Therefore, tests considering physiological and biomechanical determinants of rugby gestures should be used for fatigue monitoring.

The relationship between laboratory-based ergometer performance, body size, and on-water outrigger canoe (OC) racing remains unclear. This study examined associations between anthropometric characteristics, ergometer-derived performance, and on-water endurance performance in OC athletes using a sex-specific approach. Competitive paddlers (22 males and 16 females) completed anthropometric assessments, an incremental test, a 1000-m time trial, and a maximum paddling power test on an OC-adapted ergometer, as well as a 4.18-km simulated on-water race. Sex-specific statistical analyses, including allometric scaling and regression models, were used to identify determinants of on-water performance. Male athletes exhibited greater body mass, height, lean body mass, and superior performance in all ergometer and on-water tests compared with females (p < 0.01). In females only, body mass and lean body mass were moderately to strongly associated with ergometer-derived power outputs (r = 0.66-0.85, p < 0.01), whereas no such relationships were observed in males. Significant allometric scaling effects were identified exclusively in females for power-based ergometer variables, indicating disproportionate increases in power with increasing body and lean mass. No anthropometric variables were associated with on-water performance in either sex. In regression analyses, incremental peak power was the strongest predictor of on-water performance in males (adjusted R2 = 0.69), whereas in females, 1000-m mean power allometrically adjusted for body mass best predicted on-water speed (adjusted R2 = 0.67). These findings emphasize the importance of sex-specific interpretation of ergometer assessments and consideration of body size when relating laboratory performance to real-world OC racing.

Raimundo, JAG, Tramontin, AF, Martins, EC, Borszcz, FK, Turnes, T, de Aguiar, RA, and Caputo, F. Reliability of time spent near Vo(2)max during 2 cycling interval training sessions: the effect of Vo(2)max criteria. J Strength Cond Res 39(9): e1067-e1074, 2025-This study aimed to determine the reliability of the time spent near Vo(2)max (tVo(2)max) during 2 work-matched cycling interval trainings and to compare tVo(2)max reliability using different Vo(2)max criteria. Fifteen healthy males participated in this cross-sectional and crossover study. The participants performed on different days, an incremental ramp test followed by a Vo(2)max verification test, and a test-retest model to analyze tVo(2)max during 2 distinct work-matched interval training sessions. The interval training protocols comprised 5 x 2-minute efforts with 1-minute recovery (HIIT2min:1min) or 10 x 1-minute efforts with 30-second recovery (HIIT1min:30s) at 85% of the incremental peak power output, both followed by a Vo(2)max verification test. Times sustained above 90 and 95% (t95Vo(2)max) of Vo(2)max were analyzed and were compared based on 3 different criteria: (a) Vo(2)max from incremental and verification test (Vo(2)max(INC-VER)); (b) Vo(2)max from the verification test on the training day (Vo(2)max(DAY)); and (c) mean Vo(2)max from Vo(2)max(INC-VER) and Vo(2)max(DAY). There were no significant differences in test-retest tVo(2)max; the only exception was t95Vo(2)max during HIIT1min:30s assessed by Vo(2)max(INC-VER). The typical error of measurement and coefficient of variation ranged from 28 to 61 seconds and 19%-35% for HIIT2min:1min, and from 21 to 66 seconds and 36%-72% for HIIT1min:30s. Vo(2)max(INC-VER) reduced tVo(2)max coefficient of variation compared with Vo(2)max(DAY) for HIIT2min:1min, but not for HIIT1min:30s. Despite similar test-retest, tVo(2)max exhibited low reliability, with no improvement when a Vo(2)max verification test was included on the training day.

Purpose: To assess the effects of cycling cadence, exercise intensity, and preload on blood lactate concentration (BLC), carbohydrate oxidation (CHO), and gross efficiency (GE) during 60-minute cycling sessions. Methods: Eleven male triathletes (age: 28.2 [9.2] y, height: 179.9 [6.0] cm, body mass: 73.1 [4.8] kg, performance level 3) completed 2 incremental load tests to determine peak power (P-peak) and 4 prolonged cycling tests including 20-minute warm-up at 40% P-peak followed by a 20-minute load phase at 60% and 70% P-peak with a subsequent cooldown at 40% P-peak, all at 60 and 100 rpm, respectively. BLC, oxygen uptake, and carbon dioxide production were measured, and GE, CHO, and the fraction of oxygen uptake utilized for CHO (relCHO) were calculated. Results: The higher cadence lowered GE and increased BLC, oxygen uptake, and CHO (P < .05). RelCHO increased with exercise intensity (P < .05), but no cadence-related increase was confirmed. CHO and relCHO were lower (P < .05) at cooldown than at warm-up without changes in BLC. Conclusions: The lack of evidence for a cadence effect on relCHO supports the suggestion that a higher cadence enables a lower CHO at given metabolic demand and given BLC, particularly at lower exercise intensity. A preload-induced decrease in CHO and relCHO may appear at unchanged availability of pyruvate and lactate as indicated by the BLC. In elite cyclists, where GE remains stable or even improves at higher cadences, the ability to sustain CHO stores by higher cadences could provide a significant performance advantage.

Abstract Raimundo, JAG, Tramontin, AF, Martins, EC, Borszcz, FK, Turnes, T, de Aguiar, RA, and Caputo, F. Reliability of time spent near V̇ o 2 max during 2 cycling interval training sessions: the effect of V̇ o 2 max criteria. J Strength Cond Res 39(9): e1067–e1074, 2025—This study aimed to determine the reliability of the time spent near V̇ o 2 max (tV̇ o 2 max) during 2 work-matched cycling interval trainings and to compare tV̇ o 2 max reliability using different V̇ o 2 max criteria. Fifteen healthy males participated in this cross-sectional and crossover study. The participants performed on different days, an incremental ramp test followed by a V̇ o 2 max verification test, and a test-retest model to analyze tV̇ o 2 max during 2 distinct work-matched interval training sessions. The interval training protocols comprised 5 × 2-minute efforts with 1-minute recovery (HIIT 2min:1min ) or 10 × 1-minute efforts with 30-second recovery (HIIT 1min:30s ) at 85% of the incremental peak power output, both followed by a V̇o 2 max verification test. Times sustained above 90 and 95% (t95V̇ o 2 max) of V̇ o 2 max were analyzed and were compared based on 3 different criteria: (a) V̇ o 2 max from incremental and verification test (V̇ o 2 max INC-VER ); (b) V̇ o 2 max from the verification test on the training day (V̇ o 2 max DAY ); and (c) mean V̇ o 2 max from V̇ o 2 max INC-VER and V̇ o 2 max DAY . There were no significant differences in test-retest tV̇ o 2 max; the only exception was t95V̇ o 2 max during HIIT 1min:30s assessed by V̇ o 2 max INC-VER . The typical error of measurement and coefficient of variation ranged from 28 to 61 seconds and 19%–35% for HIIT 2min:1min , and from 21 to 66 seconds and 36%–72% for HIIT 1min:30s . V̇ o 2 max INC-VER reduced tV̇ o 2 max coefficient of variation compared with V̇ o 2 max DAY for HIIT 2min:1min , but not for HIIT 1min:30s . Despite similar test-retest, tV̇ o 2 max exhibited low reliability, with no improvement when a V̇ o 2 max verification test was included on the training day.

ABSTRACT:Meira, Â, Ferreira Tramontin, A, Ribeiro, G, Santos de Oliveira Cruz, R, Alves de Aguiar, R, Klitzke Borszcz, F, and Caputo, F. Neuromuscular performance impairment: Exploring the power-force-velocity recovery profiles in local and nonlocal muscles. J Strength Cond Res 40(1): e9-e16, 2026-This study examined the effects of neuromuscular impairment on the time course of changes in the force-velocity-power profile in local (i.e., lower limb, assessed through back squat [SQ]) and nonlocal (i.e., upper limb, assessed through bench press [BP]) muscle groups following a repetitive lengthening protocol (RLP). Sixteen physically active men (age: 23 ± 3 years; 1 maximum repetition SQ relative to body mass: 1.5 ± 0.4 kg·kg -1 ) performed an RLP involving 5 sets of maximal 25 drop jumps designed to induce neuromuscular disruption. Back squat and BP exercises were used to assess neuromuscular performance changes in local and nonlocal muscles, respectively, by means of maximal theoretical force (F 0 ), velocity (V 0 ), and power output (Pmax) at baseline and at 24, 48, and 72 hours post-RLP. Delayed onset muscle soreness was measured at 0, 24, 48, and 72 hours. Significant reductions in F 0 and Pmax were observed in both exercises, with greater impairments in the SQ ( p ≤ 0.0001). V 0 was reduced in the SQ and remained unchanged in the BP, SQ change differed significantly from BP ( p = 0.008). F 0 remained suppressed across all time points ( p < 0.001), Pmax exhibited progressive reductions, peaking at 72 hours ( p = 0.001). Delayed onset muscle soreness peaked at 48 hours and resolved by 72 hours. These findings demonstrate that RLP impairs neuromuscular performance beyond the directly affected muscles, with persistent force deficits and task-specific reductions in velocity and power. This underscores the importance of monitoring both local and nonlocal muscles recovery kinetics when designing training and rehabilitation protocols.

Purpose: This study aimed to compare the performance-derived parameters utilizing isolinear (ISOLIN) and isovelocity (ISOVEL) sprint cycling modes. Method: For that, 20 male trained cyclists performed 2 sprints of 7 s on an electromagnetically braked cycle ergometer in ISOLIN and six sprints in ISOVEL mode with cadences between 90 and 180 rpm, each separated by 3-min. A linear function modeled the sprints within each mode to extrapolate maximal cadence (CMAX) and torque (TMAX), and a quadratic function was used to extrapolate the apex defined as optimal cadence power (OPTCAD) and peak power output (PMAX). Fifteen subjects performed another 4 sprints at ISOLIN mode on different days to verify the reliability. Results: The measures from the power-cadence relationship were not different between the ISOLIN and ISOVEL modes. Although significant differences were detected in the T-C relationship, TMAX was greater at ISOLIN than ISOVEL (p = .006). On the other hand, CMAX was higher at ISOVEL than ISOLIN (p < .001). The correlation between parameters was large to very large (r = 0.51 to 0.89). However, high limits of agreement were verified. The ISOLIN presented consistency during the trials, and the random errors were acceptable (CV = 5.3% to 11.5%). Conclusion: Using the power-cadence relationship, PMAX and OPTCAD could be detected similarly between the two sprint modes (ISOLIN and ISOVEL). Thus, the findings demonstrated that a single ISOLIN sprint test could be a suitable tool for quantifying the time course of muscle fatigue during and after cycling exercises in well-trained male cyclists.

We investigated fatigue and performance rates as decision-making criteria in pacing control during CrossFit ® . Thirteen male regional-level competitors completed conditions of all-out (maximum physical work from beginning to end) and controlled-split (controlled physical work in the first two rounds but maximum work in the third round) pacing throughout the Fight Gone Bad workout separated by one week. We assessed benchmarks, countermovement jumps and ratings of fatigue after each round. Benchmarks were lower in round 1 (99 vs. 114, p < .001) but higher in rounds 2 (98 vs. 80, p < .001) and 3 (97 vs. 80, p < .001) for controlled-split compared with all-out pacing. Reductions in countermovement jumps were higher after rounds 1 (−12.6% vs. 1.6%, p < .001) and 2 (−12.7% vs. −4.0%, p = .014) but similar after round 3 (−13.2% vs. −11.3%, p = .571) for all-out compared with controlled-split pacing. Ratings of fatigue were higher after rounds 1 (7 vs. 5 a.u., p < .001) and 2 (8 vs. 7 a.u, p = .023) but similar after round 3 (9 vs. 9 a.u., p = .737) for all-out compared with controlled-split pacing. During all-out pacing, countermovement jump reductions after round 2 correlated with benchmark drops across rounds 1 and 2 ( r = .78, p = .002) and rounds 1 and 3 ( r = −.77, p = .002) and with benchmark workout changes between pacing strategies ( r = −.58, p = .036), suggesting that the larger the countermovement jump reductions the higher the benchmark drops across rounds and workouts. Therefore, benchmarks, countermovement jumps and ratings of fatigue may assess exercise-induced fatigue as decision-making criteria to improve pacing strategy during workouts performed for as many repetitions as possible.

The enigmatic benefits of acute limb ischemic preconditioning (IP) in enhancing muscle force and exercise performance have intrigued researchers. This study sought to unravel the underlying mechanisms, focusing on increased neural drive and the role of spinal excitability while excluding peripheral factors. Soleus Hoffmann (H)-reflex /M-wave recruitment curves and unpotentiated supramaximal responses were recorded before and after IP or a low-pressure control intervention. Subsequently, the twitch interpolation technique was applied during maximal voluntary contractions to assess conventional parameters of neural output. Following IP, there was an increase in both maximum normalized force and voluntary activation (VA) for the plantar flexor group, with negligible peripheral alterations. Greater benefits were observed in participants with lower VA levels. Despite greater H-reflex gains, soleus volitional (V)-wave and sEMG amplitudes remained unchanged. In conclusion, IP improves muscle force via enhanced neural drive to the muscles. This effect appears associated, at least in part, to reduced presynaptic inhibition and/or increased motoneuron excitability. Furthermore, the magnitude of the benefit is inversely proportional to the skeletal muscle's functional reserve, making it particularly noticeable in under-recruited muscles. These findings have implications for the strategic application of the IP procedure across diverse populations.

Purpose: The present study aimed to analyze: 1) the reliability of the tissue saturation index (TSI) and ratings of perceived discomfort (RPD) responses wearing a neoprene practical cuff (PrC), comparing with the responses from traditional (TrC) pneumatic cuffs (study I); 2) the effects of PrC on metabolic (blood lactate concentration, BLC), perceptual (rate of perceived effort, RPE) and kinematic responses at sub-maximal swimming velocities (study II). Methods: Study I; 1) PrC test-retest at rest and during swimming ergometer exercise; 2) BFR at rest with TrC inflated to different percentages of the minimum arterial occlusion pressure (MAOP; 60, 80, 100, 120 and 140%). Test-retest reliability of TSI and RPD was assessed by the intraclass correlation coefficient (ICC) and comparisons among conditions were analyzed by one-way repeated-measures ANOVA. Study II; 1) 50, 200 and 400 m swimming performances; 2) sub-maximal incremental swimming protocol with and without PrC. Two-way repeated measures ANOVA was used to compare all variables during sub-maximal velocities. Results: TSI (ICC = 0.81; 95%CI 0.62-0.91) and RPD (ICC = 0.97; 95%CI 0.94-0.99) were reliable under restricted exercise using PrC. TSI during restricted exercise was lower (p <.001) compared to unrestricted exercise (6.8 ± 6.1% vs. 21.6 ± 8.2% of physiological normalization). PrC showed higher BLC only at or above 91% of critical velocity (p < .03), while stroke rate and RPE were higher (p < .005), and stroke length was lower (p < .03) during all swimming velocities. Conclusion: This easy-to-handle and affordable practical BFR device increased physiological stress at sub-maximal efforts which could be an additional training tool for swimmers.

This study aimed to assess the predictive capability of different critical power (CP) models on cycling exercise tolerance in the severe- and extreme-intensity domains. Nineteen cyclists (age: 23.0 ± 2.7 y) performed several time-to-exhaustion tests (Tlim) to determine CP, finite work above CP (W'), and the highest constant work rate at which maximal oxygen consumption was attained (IHIGH). Hyperbolic power-time, linear power-inverse of time, and work-time models with three predictive trials were used to determine CP and W'. Modeling with two predictive trials of the CP work-time model was also used to determine CP and W'. Actual exercise tolerance of IHIGH and intensity 5% above IHIGH (IHIGH+5%) were compared to those predicted by all CP models. Actual IHIGH (155 ± 30 s) and IHIGH+5% (120 ± 26 s) performances were not different from those predicted by all models with three predictive trials. Modeling with two predictive trials overestimated Tlim at IHIGH+5% (129 ± 33 s; p = 0.04). Bland-Altman plots of IHIGH+5% presented significant heteroscedasticity by all CP predictions, but not for IHIGH. Exercise tolerance in the severe and extreme domains can be predicted by CP derived from three predictive trials. However, this ability is impaired within the extreme domain.

The goal of this study was to investigate the effects of photobiomodulation therapy (PBMT) on performance, oxygen uptake (VO2) kinetics, and lower limb muscle oxygenation during three successive time-to-exhaustions (TTEs) in cyclists. This was a double-blind, randomized, crossover, placebo-controlled trial study. Sixteen cyclists (~23 years) with a cycling training volume of ~460 km/week volunteered for this study. In the first session, cyclists performed a maximal incremental test to determine maximal oxygen uptake and maximal power output (POMAX). In the following sessions, cyclists performed three consecutive TTEs at POMAX. Before each test, PBMT (135 J/thigh) or a placebo (PLA) was applied to both thighs. VO2 amplitude, O2 deficit, time delay, oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb), and total hemoglobin (tHb) were measured during tests on the right vastus lateralis. The PBMT applied before three successive TTE increased performance of the first and second TTE (~10–12%) tests, speed of VO2 and HHb kinetics during the first test, and increased peripheral muscle oxygenation (increase in HHb and tHb) in the first and second exhaustion tests. However, the PBMT effects were attenuated in the third TTE, as performance and all the other outcomes were similar to the ones from the PLA intervention. In summary, PBMT application increased the first and second successive TTEs, speed of VO2, and muscle oxygenation.

What is the central question of this study? What is the reliability of near‐infrared spectroscopy‐derived muscle oxygen uptake ( mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ ) kinetics following running exercise and what is the relationship between the time constant of mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ off‐kinetics and parameters of aerobic fitness? What is the main finding and its importance? The time constant of mV̇O2${\rm{m}}{\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ kinetics in gastrocnemius following moderate running exercise presents good to excellent reliability. In addition, it was well correlated with parameters of aerobic fitness, such as maximal speed of an incremental test, ventilatory threshold and pulmonary V̇O2${\dot{V}_{{{\rm{O}}_{\rm{2}}}}}$ on‐kinetics. Therefore, near‐infrared spectroscopy‐derived muscle oxidative capacity together with other physiological measurements may allow a concomitant local and systemic analysis of the components of the oxidative system.

In swimming, the speed-time relationship provides the critical speed (CS) and the maximum distance that can be performed above CS (D′). During intermittent severe intensity exercise, a complete D′ depletion coincides with task failure, while a sub-CS intensity is required for D′ reconstitution. Therefore, determining the balance D′ remaining at any time during intermittent exercise (D'BAL) could improve training prescription. This study aimed to 1) test the D'BAL model for swimming; 2) determine an equation to estimate the time constant of the reconstitution of D' (τD′); and 3) verify if τD′ is constant during two interval training sessions with the same work intensity and duration and recovery intensity, but different recovery duration. Thirteen swimmers determined CS and D′ and performed two high-intensity interval sessions at a constant speed, with repetitions fixed at 50 m. The duration of passive recovery was based on the work/relief ratio of 2:1 (T2:1) and 4:1 (T4:1). There was a high variability between sessions for τD' (coefficient of variation of 306%). When τD′ determined for T2:1 was applied in T4:1 and vice versa, the D'BAL model was inconsistent to predict the time to exhaustion (coefficient of variation of 29 and 28%). No linear or nonlinear relationships were found between τD′ and CS, possibly due to the high within-subject variability of τD'. These findings suggest that τD′ is not constant during two high-intensity interval sessions with the same recovery intensity. Therefore, the current D'BAL model was inconsistent to track D′ responses for swimming sessions tested herein.

PURPOSE:The aim of this study was to identify a blood-flow-restriction (BFR) endurance exercise protocol that maximizes metabolic strain and minimizes muscle fatigue. METHODS:Twelve healthy participants accomplished 5 different interval cycling endurance exercises (2-min work, 1-min rest) in a randomized order: (1) control, low intensity with unrestricted blood flow (CON30); (2) low intensity with intermittent BFR (i-BFR30, ∼150 mm Hg); (3) low intensity with continuous BFR (c-BFR, ∼100 mm Hg); (4) unloaded cycling with i-BFR0 (∼150 mm Hg); and (5) high intensity (HI) with unrestricted blood flow. Force production, creatine kinase activity, antioxidant markers, blood pH, and potassium (K+) were measured in a range of 5 minutes before and after each cycling exercise protocol. RESULTS:HI showed the highest reduction (Δ = -0.26 [0.05], d = 5.6) on blood pH. Delta pH for c-BRF30 (Δ = -0.02 [0.03], d = 0.8) and Δ pH for i-BRF30 (Δ = -0.04 [0.03], d = 1.6) were different from each other, and both were higher compared with CON30 (Δ = 0.03 [0.03]). There was significant before-to-after force loss following HI (Δ = 55 [40] N·m-1, d = 1.5) and c-BFR30 (Δ = 27 [21] N·m-1, d = 0.7) protocols only, which were accompanied by significant increases in K+ (HI: Δ = 0.94 [0.65] mmol·L-1, d = 1.8; c-BFR30: Δ = 0.72 [0.85] mmol·L-1, d = 1.2). Moreover, all BFR conditions elicited slight increases in plasma creatine kinase, but not for HI and CON30. Glutathione changes from before to after were significant for all BFR conditions and HI, but not for CON30. CONCLUSIONS:The attenuation in fatigue-induced reductions in maximal force suggests that i-BFR exercise could be preferable to c-BFR in improving exercise capacity, with considerably less biologic stress elicited from HI exercises.

Objective. -This study aimed to correlate the physiological and neuromuscular parameters with the Jiu-Jitsu Anaerobic Performance Test (JJAPT). Methods. -Fourteen male Brazilian Jiu-Jitsu (BJJ) athletes (27.3 +/- 3.7 years) participated in this study. The athletes were assessed on three occasions separated by 48-hour intervals: a) vertical jump and incremental tests; b) isokinetic evaluation of hip flexor muscles and the Wingate test; c) JJAPT. Analysis of variance for repeated measures was used to compare the JJAPT repetitions and rate of perceived exertion (RPE) over the test, and the Pearson correlation was used to verify the relationship between JJAPT performance, physiological and neuromuscular variables. Results. -There was a significant decrease of JJAPT repetitions especially from the fourth set (P = 0.001) and an increase of RPE (P < 0.001) over the sets. The JJAPT repetitions were not correlated with neuromuscular and the Wingate anaerobic test parameters (r = -0.06 to 0.24; P > 0.05). Mean JJAPT repetitions were significantly higher (P = 0.01) in the advanced (18 +/- 2 reps) compared to the novice repetitions (15 +/- 2 reps). Conclusion. -Advanced athletes showed higher JJAPT performance than novice, but not higher physical performance when assessed by neuromuscular, aerobic and anaerobic tests. The physical tests results were not correlated with JJAPT performance. Thus, it is possible to suggest that JJAPT showed higher sensitivity to discriminate BJJ athletes than traditional cycle ergometer fitness tests. (C) 2021 Published by Elsevier Masson SAS.

Ribeiro, G, de Aguiar, RA, Penteado, R, Lisboa, FD, Raimundo, JAG, Loch, T, Meira, a, Turnes, T, and Caputo, F. A-mode ultrasound reliability in fat and muscle thickness measurement. J Strength Cond Res 36(6): 1610-1617, 2022-This study aimed to verify the reliability of the BodyMetrix portable A-mode ultrasound in measuring fat and muscle tissue thickness. Thirty physically active men participated in daily body composition evaluations. The evaluations comprised 2 techniques: (a) graphic technique (GT(BM)), which measured the fat thickness at 9 body sites (abdomen, axillary, biceps brachii, calf, chest, subscapular, suprailiac, thigh, and triceps brachii), and (b) imaging technique (ITBM), which simultaneously measured the fat and muscle thickness of 6 body surfaces (abdomen, biceps brachii, chest, thigh, trapezius, and triceps brachii). Regarding GT(BM), relative reliability was moderate to excellent (intraclass correlation coefficient [ICC]: 0.81-0.98), whereas absolute reliability was acceptable for abdomen, calf, chest, subscapular, suprailiac, and triceps brachii (coefficient of variation [CV]: 6.9-8.8%) but high for axillary, biceps brachii, and thigh (CV: 12.0-17.4%) in measuring fat thicknesses. Concerning ITBM, relative reliability was good to excellent (ICC: 0.93-0.99 and 0.90-0.98), whereas absolute reliability was acceptable (CV: 3.0-9.2% and 3.5-5.9%) in measuring fat and muscle thickness, respectively. These findings suggest that the, GT(BM) was only reliable in measuring fat thickness of abdomen, calf, chest, subscapular, suprailiac, and triceps brachii, whereas ITBM was reliable in measuring both fat and muscle thickness in all regions, but showed better reliability values in measuring muscle than fat thickness.

Abstract Objective to provide test-retest reliability for the TGlittre-P in children and adolescents with cystic fibrosis (CFG) and healthy controls (HCG), to establish the minimal detectable change for time in TGlittre-P and comparing the performance in the TGlittre-P test between these populations. Method A cross-sectional study evaluated 36 children and adolescents aged 6 to 13. Anthropometric and spirometric evaluation was performed, as well as, on the same day, two TGlittre-P tests with a 30-minute interval between them. Results TGlittre-P time test-retest reliability was excellent for both groups (CFG: intraclass correlation coefficient [ICC] = 0.849, p < 0.001 and HCG: ICC = 0.913, p < 0.001). As concerning absolute reliability, the time spent presented a small variability with a standard error of measurement of 8.4 s (s) to CFG and 5.3 s to HCG. The minimal detectable change at 95% confidence level (MDC95) was 23.2 s and 14.6 s, respectively. There was no difference between the groups regarding performance in the TGlittre-P test (CFG 179.1 s ± 25.7 s vs. HCG 174.7 s ± 22.3 s) p = 0.589. Conclusion The TGlittre-P is a reliable tool in children and adolescents with CF and healthy controls. The TGlittre-P appears not to be sensitive enough to discriminate a group of children and adolescents with mild cystic fibrosis from healthy counterparts. IMPLICATIONS FOR REHABILITATION TGlittre-P is a multitasking test that has been used to assess the functional capacity of children and adolescents with chronic diseases. TGlittre-P has excellent reliability in children and adolescents with and without CF. TGlittre-P differences time greater than 12% could indicate changes in the functional capacity of children and adolescents with CF. Other functional capacity tests may be preferred to detect continuous increases in functional capacity through rehabilitation or training, whether children and adolescents obtain performance values close to 100% of predicted.

STUDY DESIGN:This was a transversal analytical study. BACKGROUND:Exercise capacity is usually decreased in cystic fibrosis, impacting the disease prognosis. As well, peripheral muscle strength and nutritional status seem to be related to exercise capacity (EC). OBJECTIVE:To verify the relationship between peripheral muscle strength, pulmonary function and body composition with EC in children and adolescents with CF. METHODS:The study included CF children/adolescents that were clinically stable. The disease's severity was classified according to the Schwachman-Doerschuk score. Initially the subjects underwent bioimpedance and spirometry tests. Quadriceps muscle strength (QMS) and handgrip strength (HG) were evaluated by dynamometry. The Modified Shuttle Walk Test (MSWT) was conducted along with gas analysis in order to measure EC. RESULTS:Twenty-five children/adolescents (10.30 ± 2.33 years old) participated in the survey. 72% were eutrophic, with a mean FEV1 of 68.55%, predicted percentage of the MSWT walked distance (%WD) was 70.91%, and QMS 65.80%. QMS presented significant correlations with absolute WD (r = 0.54), oxygen peak consumption (r = 0.72), lean body mass (LM) (r = 0.83), and body mass index (BMI) (r = 0.69). HG was related with BMI (r = 0.45) and LM (r = 0.65). There was a difference in the %WD between the groups with higher/lower strength (p = .02). CONCLUSION:There was no correlation between HG and EC in this studied sample. Early involvement of QMS was observed even in individuals with low disease severity. This finding reinforces the importance of including this QMS assessment in CF reference centers to monitor, prevent and prescribe adequate exercise training for these individuals.

Lisboa, FD, Raimundo, JAG, Pereira, GS, Ribeiro, G, de Aguiar, RA, and Caputo, F. Effects of time of day on race splits, kinematics, and blood lactate during a 50-m front crawl performance. J Strength Cond Res 35(3): 819-825, 2021-This study aimed to investigate the performance, race splits, metabolic, and stroke parameters during 2 successive 50-m front crawl under conditions simulating a competition. Eleven competitive male swimmers (20 +/- 3 years, 182 +/- 5 cm, and 77 +/- 5 kg) performed 2 successive 50-m front crawl trials in a 50-m swimming pool at 10 am and 5 pm. Block time (tB), 15-m performance (t.15-m), and 50-m performance (t.50-m) were measured. Velocity (V), stroke rate (SR), stroke length (SL), and stroke index (SI) were measured at 3 time points during the trials. Pre-trial and post-trial blood samples were taken to determine blood lactate accumulation (Delta[Lac]). For t.50-m, the relative difference between 10 am and 5 pm reached 0.1% (p = 0.7; effect size [ES] = 0.02). Furthermore, no differences in tB (p = 0.12; ES = -0.28) and t.15-m (p = 0.39; ES = -0.16) were observed between periods. Both V (p = 0.11; ES = -0.14) and SI (p = 0.16; ES = 0.15) were also similar. Higher values of SR were recorded at 10 am (p = 0.03; ES = -0.32), whereas the morning values of SL were lower (p = 0.04; ES = 0.3). Delta[Lac] was not significantly different between periods (p = 0.07; ES = -0.27). Although time of the day did not impact performance in 2 successive 50-m front crawl performances, different stroke parameters profiles were observed during these trials. This may help coaches design specific warm-up exercises to enhance performance at different times of the day.