Cycling Sprint Test Research Articles

Dose-response effects of caffeine during repeated cycling sprints in normobaric hypoxia to exhaustion.

With limited studies exploring the dose-response of caffeine consumption on repeated sprint ability in hypoxia, this study aimed to determine the optimal caffeine dose (low, moderate or high) during repeated sprints in hypoxia to exhaustion. On separate visits, twelve active males randomly performed four experimental trials in normobaric hypoxia (inspired oxygen fraction: 16.5 ± 0.2%). Participants ingested placebo (PLA) or caffeine capsules (3, 6 or 9mg/kg or LOW, MOD and HIGH, respectively) 1h before exercise and then underwent a repeated cycling sprint test (10s sprint/20s active recovery) to exhaustion. Total sprint number and work done, peak and mean power output, blood lactate concentration, cardiorespiratory and perceptual responses were recorded. Total sprint number was greater in MOD and HIGH compared to PLA (20 ± 7 and 18 ± 8 vs. 13 ± 4; all P < 0.05), with MOD also higher than LOW (15 ± 6; P = 0.02). Total work done was greater in MOD (111 ± 40kJ) and HIGH (100 ± 35kJ) compared to LOW (83 ± 29kJ) and PLA (76 ± 25kJ) (all P < 0.05). However, there were no significant differences in total sprint number or total work done between MOD and HIGH (all P > 0.05). Blood lactate concentration was higher in both MOD and HIGH compared to PLA (all P < 0.05). However, peak and mean power outputs, fatigue index, and ratings of perceived exertion did not differ across different caffeine dosages (all P > 0.05). A moderate dose of caffeine (6mg/kg) is the optimal amount for enhancing repeated cycling sprint ability when compared to low and high doses in moderate normobaric hypoxia.

Relationship of peak capillary blood lactate accumulation and body composition in determining the mechanical energy equivalent of lactate during sprint cycling

AimA 15-s all-out sprint cycle test (i.e., νLamax-test) and the post-exercise change in capillary blood lactate concentration is an emerging diagnostic tool that is used to quantify the maximal glycolytic rate. The goal of this study was to determine the relation between 15 s-work, change in capillary blood lactate concentration (∆La) and body composition in a νLamax-test.MethodFifty cyclists performed a 15 s all-out sprint test on a Cyclus2 ergometer twice after a previous familiarization trial. Capillary blood was sampled before and every minute (for 8 min) after the sprint to determine ∆La. Body composition was determined employing InBody720 eight-electrode impedance analysis.ResultSimple regression models of fat-free mass (FFM) and also the product of FFM and ∆La showed similar ability to predict 15 s-work (R2 = 0.79; 0.82). Multiple regression combining both predictors explains 93% of variance between individuals. No differences between males and females were found regarding 15 s-work relative to the product of fat-free mass and ∆La. Considering pairs of similar FFM, a change 1 mmol/l of ∆La is estimated to be equal to 12 J/kg in 15 s-work (R2 = 0.85).DiscussionFifteen s-work is both closely related to FFM and also the product of ∆La and lactate-distribution space approximated by FFM. Differences in 15 s-work between males and females disappear when total lactate production is considered. Considering interindividual differences, the mechanical energy equivalent of blood lactate accumulation seems a robust parameter displaying a clear relationship between ∆La and 15 s-work relative to FFM.

Effects of Hormonal Contraception and the Menstrual Cycle on Fatigability and Recovery From an Anaerobic Exercise Test.

Cabre, HE, Ladan, AN, Moore, SR, Joniak, KE, Blue, MNM, Pietrosimone, BG, Hackney, AC, and Smith-Ryan, AE. Effects of hormonal contraception and the menstrual cycle on fatigability and recovery from an anaerobic exercise test. J Strength Cond Res 38(7): 1256-1265, 2024-This study sought to evaluate the effects of oral contraceptive (OC) and hormonal intrauterine device (H-IUD) use, compared with a eumenorrheic (EUM) cycle, on fatigability and recovery between hormone the phases. Peak power (PP), average power (AP), fatigue index (FI), blood lactate, vessel diameter, and blood flow (BF) were measured from a repeated sprint cycle test (10 × 6 seconds) in 60, healthy, active women (mean ± SD ; age: 26.5 ± 7.0 years, BMI: 22.5 ± 3.7 kg·m -2 ) who used monophasic OC (≥6 months; n = 21), had a H-IUD (≥6 months; n = 20), or had regular naturally occurring menstrual cycle (≥3 months) or had a nonhormonal IUD (EUM; n = 19). Subjects were randomly assigned to begin in either the low-hormone phase (LHP) or high-hormone phase (HHP) and were tested once in each phase. Separate univariate analyses of covariances assessed the change from HHP to LHP between the groups, covaried for progesterone, with significance set at p ≤ 0.05. All groups demonstrated similar changes in PP, AP, FI, blood lactate, vessel diameter, and BF between the phases ( p > 0.05). Although not significant, AP was higher in LHP for OC (Δ -248.2 ± 1,301.4 W) and EUM (Δ -19.5 ± 977.7 W) and higher in HHP for H-IUD (Δ 369.3 ± 1,123.0 W). Oral contraceptive group exhibited a higher FI (Δ 2.0%) and reduced blood lactate clearance (Δ 2.5%) in HHP. In recreationally active women, hormonal contraception and hormone phases may minimally impact fatigue and recovery. Individual elite female athletes may benefit from understanding hormonal contraception type as performance and recovery may slightly vary across the cycle.

Lamax: determining the optimal test duration for maximal lactate formation rate during all-out sprint cycle ergometry.

This study aimed to ascertain the optimal test duration to elicit the highest maximal lactate formation rate ( Lamax), whilst exploring the underpinning energetics, and identifying the optimal blood lactate sampling period. Fifteen trained to well-trained males (age 27 ± 6years; peak power: 1134 ± 174W) participated in a randomised cross-over design completing three all-out sprint cycling tests of differing test durations (10, 15, and 30s). Peak and mean power output (W and W.kg-1), oxygen uptake, and blood lactate concentrations were measured. Lamax and energetic contributions (phosphagen, glycolytic, and oxidative) were determined using these parameters. The shortest test duration of 10s elicited a significantly (p = 0.003; p < 0.001) higher Lamax (0.86 ± 0.17mmol.L-1.s-1; 95% CI 0.802-0.974) compared with both 15s (0.68 ± 0.18mmol.L-1.s-1; 95% CI 0.596-0.794) and 30s (0.45 ± 0.07mmol.L-1.s-1; 95% CI 0.410-0.487). Differences in Lamax were associated with large effect sizes (d = 1.07, d = 3.15). We observed 81% of the PCr and 53% of the glycolytic work completed over the 30s sprint duration was attained after 10s. BLamaxpost were achieved at 5 ± 2min (ttest 10s), 6 ± 2min (ttest 15s), and 7 ± 2min (ttest 30s), respectively. Our findings demonstrated a 10s test duration elicited the highest Lamax. Furthermore, the 10s test duration mitigated the influence of the oxidative metabolism during all-out cycling. The optimal sample time to determine peak blood lactate concentration following 10s was 5 ± 2min.

Reliability of the 15-s Maximal Lactate Accumulation Rate (VLamax) Test for Cycling

Background: The purpose of this study is to ascertain the reliability of two 15-s sprint cycling tests in men and women to estimate the maximum lactate accumulation rate (VLamax). Methods: Eighteen men and twelve women completed two sprint sessions over 1 week. A 10 min warm-up preceded the obtaining of a 3 µL blood lactate (BLC) sample, after which a 15 s sprint was completed; cyclists then rested passively while multiple lactate samples were taken until the levels peaked. Trial differences and reliability across trials were analyzed using a paired-sample t-test, Pearson’s correlation, Intraclass correlation (ICC), and Bland–Altman analysis with α = 0.05 for all tests; data are reported as mean ± sd. Results: Power (W) was similar across trials (773.0 ± 143.5 vs. 758.2 ± 127.4; p = 0.333) and the coefficient of variation (CV) of 4.7%. VLamax (mM·L−1·s−1) was similar (0.673 ± 0.024 vs. 0.635 ± 0.237; p = 0.280), but only moderately reliable across trials with CV, ICC, and R values of 18.6%, 0.661, and 0.67, respectively. Pre-BLC and peak BLC CV were 45.6 and 23.3%, respectively. Conclusions: A 15 s VLamax cycling sprint is moderately reliable, possibly affected both by the lactate measurement and other variables used in the calculation. More research may offer ways to improve reliability.

Effects of the menstrual cycle on EPOC and fat oxidation after low-volume high-intensity interval training.

Low-volume high-intensity interval training (HIIT) for weight loss has become prevalent in recent years, with increased excess post-exercise oxygen consumption (EPOC) as the mechanism. However, the influence of the menstrual cycle on EPOC and fat oxidation following low-volume HIIT is unclear. This study aimed to investigate the effect of the menstrual cycle on the increase in EPOC and fat oxidation after low-volume HIIT. Twelve eumenorrheic women participated during their early follicular and luteal phases. On each experimental day, they performed low-volume HIIT comprising fifteen repeated 8 s sprint cycling tests with 12 s rests, for 5 min. Expired gas samples were collected before and every 60 min until 180 min post-exercise. EPOC was defined as the increase in oxygen consumption from the resting state, and the total EPOC and fat oxidation were calculated from the total time of each measurement. Blood samples for serum estradiol, progesterone, free fatty acids, blood glucose, lactate, and plasma noradrenaline were collected and assessed before immediately after, and at 180 min post-exercise and were assessed. Serum estradiol and progesterone were significantly higher in the luteal phase than the follicular phase (P<0.01 for both). No significant differences in total EPOC and fat oxidation were found between the menstrual phases. Serum free fatty acid, blood glucose, lactate, and plasma noradrenaline concentrations were not affected by the menstrual cycle. These results suggest that the menstrual cycle does not affect the increase in EPOC or fat oxidation after low-volume HIIT.

A modified formula using energy system contributions to calculate pure maximal rate of lactate accumulation during a maximal sprint cycling test.

Purpose: This study aimed at comparing previous calculating formulas of maximal lactate accumulation rate ( ν La.max) and a modified formula of pure ν La.max (P ν La.max) during a 15-s all-out sprint cycling test (ASCT) to analyze their relationships. Methods: Thirty male national-level track cyclists participated in this study (n = 30) and performed a 15-s ASCT. The anaerobic power output (Wpeak and Wmean), oxygen uptake, and blood lactate concentrations (La-) were measured. These parameters were used for different calculations of ν La.max and three energy contributions (phosphagen, W PCr; glycolytic, W Gly; and oxidative, W Oxi). The P ν La.max calculation considered delta La-, time until Wpeak (tPCr-peak), and the time contributed by the oxidative system (tOxi). Other ν La.max levels without tOxi were calculated using decreasing time by 3.5% from Wpeak (tPCr -3.5%) and tPCr-peak. Results: The absolute and relative W PCr were higher than W Gly and W Oxi (p < 0.0001, respectively), and the absolute and relative W Gly were significantly higher than W Oxi (p < 0.0001, respectively); ν La.max (tPCr -3.5%) was significantly higher than P ν La.max and ν La.max (tPCr-peak), while ν La.max (tPCr-peak) was lower than P ν La.max (p < 0.0001, respectively). P ν La.max and ν La.max (tPCr-peak) were highly correlated (r = 0.99; R 2 = 0.98). This correlation was higher than the relationship between P ν La.max and ν La.max (tPCr -3.5%) (r = 0.87; R 2 = 0.77). ν La.max (tPCr-peak), P ν La.max, and ν La.max (tPCr -3.5%) were found to correlate with absolute Wmean and W Gly. Conclusion: P ν La.max as a modified calculation of ν La.max provides more detailed insights into the inter-individual differences in energy and glycolytic metabolism than ν La.max (tPCr-peak) and ν La.max (tPCr -3.5%). Because W Oxi and W PCr can differ remarkably between athletes, implementing their values in P ν La.max can establish more optimized individual profiling for elite track cyclists.

Reliability and Validity of the Kickboxing Anaerobic Speed Test

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

Physiological profile of elite Bicycle Motocross cyclists and physiological-perceptual demands of a Bicycle Motocross race simulation.

This study aimed to investigate the physiological profile of elite Bicycle Motocross (BMX) cyclists and assess the physiological and perceptual demands of a simulated BMX race. In addition, the neuromuscular fatigue induced by BMX race simulation was investigated. Twelve male elite BMX cyclists performed two testing sessions. On the first day, incremental submaximal and maximal cycling tests were performed, as well as baseline measurements of muscle contractile qualities, a vertical jump test, short sprint cycling test and Wingate test. Following a recovery period of 48 h, athletes race performance times, physiological intensity and fatigue were determined before and after each heat (4 in total) via muscular evaluations, blood samples and perceptual ratings. During testing, cyclists attained a V̇O<inf>2max</inf> of 55.7±4.8 ml min-1 kg-1; peak power output during a short cycling sprint of 1498±189 W and average during Wingate of 1344±158 W; counter movement jump peaks were 58.6±7.7 cm (height), 4625±768 W (power) and 64.3±7.5 N kg-1 (force). During the BMX race simulation performance times improved slightly and perceived exertion increased, blood lactate and hydrogen ions concentrations significantly increased across heats while bicarbonate concentrations decreased (P<0.001). Similarly, significant decreases were observed for contractile properties (peak torque, P<0.001; maximal rate of torque development and relaxation, both P<0.001) at single and paired stimulations (10 and 100 Hz) across heats. Elite BMX cyclists show high anaerobic characteristics (Wingate and sprint) and neuromuscular qualities (height and power jump), while the aerobic qualities are not comparable to those typical of road cyclists. BMX races appear to induce metabolic disturbance, peripheral fatigue and increase perceived exertion, however performance times across heats appears not to be affected.

Anaerobic Power Assessment in Athletes: Are Cycling and Vertical Jump Tests Interchangeable?

Regularly assessing anaerobic power is important for athletes from sports with an explosive strength component. Understanding the differences and overlap between different assessment methods might help coaches or smaller-scale testing facilities maximize financial and temporal resources. Therefore, this study investigated the degree to which cycling sprint and vertical jump tests are interchangeable for determining peak mechanical leg power output in strength-trained athletes. Professional skiers (n = 19) performed unloaded squat jumps (SJ) and other jump forms on a force plate and a six-second cycling sprint (6sCS) test on an ergometer on six occasions over two years. Along with cross-sectional correlations between cycling and jumping power, correlations between longitudinal percent changes and agreement between magnitude-based inferences about individual changes were assessed. Among the tested jump forms, SJ reflected 6sCS best. However, despite extremely large cross-sectional correlation coefficients (0.92) between 6sCS and SJ, and moderate (Pearson’s r = 0.32 for 6sCS with SJ over one-year time spans) to large (r = 0.68 over shorter time spans) correlation coefficients on percent changes, magnitude-based inferences agreed in only around 50% of cases. Thus, for making qualitative assessments about the development of anaerobic power over time in athletes, cycling sprint and squat jump tests are not interchangeable. Rather, we recommend employing the test form that best reflects athletes’ strength and conditioning training.

Isovelocity vs. Isoinertial Sprint Cycling Tests for Power- and Torque-cadence Relationships.

Sprint cycling performance is heavily dependent on mechanical peak power output (PPO) and the underlying power- and torque-cadence relationships. Other key indices of these relationships include maximum torque (TMAX), cadence (CMAX) and optimal cadence (COPT). Two common methods are used in the laboratory to ascertain PPO: isovelocity and isoinertial. Little research has been carried out to compare the magnitude and reliability of these performance measures with these two common sprint cycling assessments. The aim of this study was to compare the magnitude and reliability of PPO, TMAX, CMAX and COPT measured with isovelocity and isoinertial sprint cycling methods. Two experimental sessions required 20 trained cyclists to perform isoinertial sprints and then isovelocity sprints. For each method, power-cadence and torque-cadence relationships were established, and PPO and COPT were interpolated and TMAX and CMAX were extrapolated. The isoinertial method produced significantly higher PPO (p<0.001) and TMAX (p<0.001) than the isovelocity method. However, the isovelocity method produced significantly higher COPT (p<0.001) and CMAX (p=0.002). Both sprint cycling tests showed high levels of between-session reliability (isoinertial 2.9-4.4%; isovelocity 2.7-4.0%). Functional measures of isovelocity and isoinertial sprint cycling tests were highly reliable but should not be used interchangably.

Enhanced Strength, Power, Work Capacity, and Fatigue Resistance in High Intensity Functional Training Athletes

Measures of aerobic capacity, strength, fatigue, and power in athletes who specialize in either strength or endurance are relatively well understood. However, these measures in athletes who participate in high intensity functional training (HIFT) are comparatively unknown.PURPOSETo assess differences in aerobic capacity (VO2max), peak power (PP), end power (EP), strength (N.m), and fatigue (%change) in recreational athletes from Powerlifting and Olympic Lifting (STR), Cross Country (END) and HIFT backgrounds.METHODSTwenty‐one individuals from the three different training backgrounds were recruited (STR = 7, END = 7, HIFT = 7). Participants completed an incremental ramp, 30W/minute maximal cycle ergometer test to determine VO2max and gas exchange threshold (GET), and a 3‐minute all out sprint cycling test (3MAOT) to determine peak power (PP) and end power (EP). PP was determined as the maximal power out during the first 6s of the 3MAOT, and EP was calculated as the average power output during the last 30s. To determine strength, participants completed a maximal voluntary contraction (MVC) of the knee extensors on a Biodex at 90°, 75°, and 60° of knee flexion. A triaxial accelerometer was placed on the right vastus lateralis to measure fatigue as the %change in movement during 11‐minutes of continuous electrical stimulation separated by 30‐seconds of rest at the 9‐minute mark. Electrical stimulation consisted of doublets at a 5Hz train rate. Accelerometry data were digitally filtered with low‐pass filter at 40Hz cut off (4th order; Butterworth). Data were analyzed using a repeated measures ANOVA with results presented as mean and SD.RESULTSVO2max was significantly different between all groups (p &lt; 0.01). PP was significantly higher in STR and HIFT compared to END (p &lt; 0.05), but not between STR and HIFT. EP was significantly lower in STR compared to END and HIFT (p &lt; 0.01), but not between END and HIFT. The %change in STR during the fatigue test was significantly higher than the change observed in END and HIFT (p &lt; 0.05) but not between END and HIFT, indicating STR were more prone to fatigue than the other groups. The angle at which STR and HIFT recorded their highest peak torque was at 90° of knee flexion, whereas END peaked at 75°. Torque production at all three angles was significantly lower in END compared to STR and HIFT (p &lt; 0.05) but was not significantly different at any angle between STR and HIFT. See table 1 for mean results comparisons.ConclusionTo our knowledge, this study is the first to compare performance related measures in HIFT athletes to traditional strength and endurance specialists. The results indicate that HIFT athletes can exert similar power outputs and absolute strength compared to strength specialists but exhibit a resistance to fatigue that is comparable to endurance specialists. imageThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Reliability of traditional and task specific reference tasks to assess peak muscle activation during two different sprint cycling tests

Neuromuscular activation is considered an important determinant sprint cycling performance but requires reliable EMG amplitude measurements to facilitate sensitive assessments. The reliability of EMG measurements during sprint cycling may depend on the sprint cycling test undertaken (isovelocity or isoinertial accelerating), the reference tasks used for normalisation (isometric MVCs of a series of single muscle groups [ISO-SINGJT] or isometric cycling MVCs [ISO-CYC]), and the efficacy of the normalisation. This study aimed to compare the magnitude and between-session reliability of peak muscle activation (peak rmsEMG) during: isovelocity and isoinerital sprint cycling tests; ISO-SINGJT and ISO-CYC reference tasks; and absolute and normalised EMG during the sprint cycling tests.EMG amplitude was measured over six major muscle groups on both legs and all measurements were made over two sessions in a randomised counterbalanced design. Peak rmsEMG was assessed during both ISO-SINGJT and ISO-CYC MVCs and then during mechanical peak power output (PPO) during isovelocity (120 RPM) and isoinerital acceleration (0 to >150 RPM) sprint tests. Absolute peak rmsEMG and for the sprint tests normalised EMG values were determined, and coefficient of variation and intra-class correlation coefficients used to assess reliability.Peak rmsEMG at PPO during both sprint cycling tests was similar for the six muscle groups measured. Peak rmsEMG was higher during ISO-SINGJT than ISO-CYC for for 3 of the 6 muscle groups, but all muscle groups exhibited similar reliability for both reference tasks. Neither reference task improved the between-session reliability for either sprint test. This data highlights reservations in the use of isometric reference tasks to ascertain changes in peak muscle activation over time in during sprint cycling assessments.

Oxygenation time course and neuromuscular fatigue during repeated cycling sprints with bilateral blood flow restriction.

The aim was to evaluate changes in peripheral and cerebral oxygenation, cardiorespiratory, and performance differences, as well as neuromuscular fatigue across multiple levels of blood flow restriction (BFR) during a repeated cycling sprint test to exhaustion (RST). Participants performed three RST (10‐sec maximal sprints with 20‐sec recovery until exhaustion) with measurements of power output and V̇O2peak as well as oxygenation (near‐infrared spectroscopy) of the vastus lateralis and prefrontal cortex. Neuromuscular fatigue was assessed by femoral nerve stimulation to evoke the vastus lateralis. Tests were conducted with proximal lower limb bilateral vascular occlusion at 0%, 45%, and 60% of resting pulse elimination pressure. Total work decreased with BFR (52.5 ± 22.9% at 45%, 68.6 ± 32.6% at 60%, P < 0.01 compared with 0%) as V̇O2peak (12.6 ± 9.3% at 45%, 18.2 ± 7.2% at 60%, compared with 0%, P < 0.01). Decreased changes in muscle deoxyhemoglobin (∆[HHb]) during sprints were demonstrated at 60% compared to 0% (P < 0.001). Changes in total hemoglobin concentrations (∆[tHb]) increased at both 45% and 60% compared with 0% (P < 0.001). Cerebral ∆[tHb] increased toward exhaustion (P < 0.05). Maximal voluntary contraction (MVC), voluntary activation level (VAL), and root mean square (RMS)/M‐wave ratio decreased at 60% compared with 0% (P < 0.001, all). MVC and VAL decreased between 45% and 60% (P < 0.05, both). The application of BFR during RST induced greater changes in tissue perfusion (via blood volume, ∆[tHb]) suggesting a possible stimulus for vascular blood flow regulation. Additionally, high‐intensity sprint exercise with partial ischemia may challenge cerebral blood flow regulation and influence local fatigue development due to protection of cerebral function.

Anaerobic Exercise-Induced Activation of Antioxidant Enzymes in the Blood of Women and Men.

Objective: Physical exercise changes redox balance in the blood. The study aim is to determine gender-related differences in enzymatic antioxidant defense [superoxide dismutase, catalase (CAT), and glutathione peroxidase (GPx)] during the initial period following anaerobic exercise and 24 h after its completion.Methods: Young, non-training participants (10 women and 10 men) performed a single anaerobic exercise, which was a 20-s maximal cycling sprint test. Blood was collected before and after completing the anaerobic exercise, i.e., after 3, 15, 30, and 60 min and after 24 h. Lactate concentration, and the superoxide dismutase, CAT, and GPx activity were determined. The results were adapted to the changes in plasma volume.Results: Anaerobic exercise induced a significant increase in lactate concentration, similar among both sexes. Anaerobic exercise evokes identical changes in the activity of antioxidant enzymes in the blood plasma of women and men, which is dependent on anaerobic capacity. In the early phase of restitution, the activity of antioxidant enzymes decreases; 24 h after anaerobic exercise, GPx activity in the blood plasma of women and men is higher than before the exercise.Conclusion: There are no gender-related differences concerning changes in plasma antioxidant activity after anaerobic exercise. Depending on the antioxidant enzyme, changes of activity differ in time after the end of the anaerobic exercise.

The influence of somatotype on anaerobic performance.

The link between athlete physique and performance in sports is well established. However, a direct link between somatotype three-numeral rating and anaerobic performance has not yet been reported. The purpose of this study was to assess the relations between somatotype and anaerobic performance using both singular and multivariate analyses. Thirty-six physically active males (mean ± standard deviation age 26.0 ± 9.8 years; body mass 79.5 ± 12.9 kg; height 1.82 ± 0.07 m) were somatotype-rated using the Heath-Carter method. Subjects were assessed for 3 repetition maximum (3 RM) bench press and back squat, and completed a 30-second maximal sprint cycle test. Positive correlations were observed between mesomorphy and 3 RM bench press (r = 0.560, p < 0.001), mesomorphy and 3 RM back squat (r = 0.550, p = 0.001) and between mesomorphy and minimum power output (r = 0.357, p = 0.033). Negative correlations were observed between ectomorphy and 3 RM bench press (r = -0.381, p = 0.022), and ectomorphy and 3 RM back squat (r = -0.336, p = 0.045). Individual regression analysis indicated that mesomorphy was the best predictor of 3 RM bench press performance, with 31.4% of variance in 3 RM bench press performance accounted for by the mesomorphy rating (p < 0.001). A combination of mesomorphy and ectomorphy best predicted 3 RM back squat performance (R2 = 0.388, p < 0.04). Around one third of strength performance is predicted by somatotype-assessed physique in physically active males. This could have important implications for the identification of those predisposed to perform well in sports containing strength-based movements and prescription of training programmes.

Reliability of a laboratory-based long sprint cycling test: applications of the smallest worthwhile changes in performance for repeated measures designs

The aims of the present study were to assess the reliability of long sprint cycling performance in a group of recreationally trained cyclists and to provide thresholds for changes in performance for this particular group of subjects in repeated measures designs through a scale of magnitudes. Repeatability of mean power output during a 1-min cycling time trial was assessed in a group of 15 recreationally trained cyclists (26 ± 5, years, 176 ± 5 cm, 78 ± 8 kg). They were tested on separate days, approximately one week apart. The test and retest values for the whole group of cyclists were 7.0 ± 0.5 W/kg and 6.9 ± 0.6 W/kg (systematic change and 90% confidence limits of -1.0% ± 1.1%). Our results indicated good test-retest reproducibility (typical error of 1.8%, 90% confidence limits of 1.4% to 2.6%; intraclass correlation coefficient of 0.96, confidence limits of 0.91 to 0.99), but suggested a reduction of mean power for the “slower” subjects on retest (-2.0%, 90% confidence limits of ±1.8%). If not monitored, this systematic decrease could interfere in results of studies utilizing groups with similar performance levels, particularly investigating strategies to improve performance in sprint cycling exercises around 1 min. The thresholds for moderate, large, very large and extremely large effects for mean power output on long sprint cycling performance are about 0.4%, 1.3%, 2.3%, 3.6%, and 5.8%, respectively.

Changes in Muscle and Cerebral Deoxygenation and Perfusion during Repeated Sprints in Hypoxia to Exhaustion.

During supramaximal exercise, exacerbated at exhaustion and in hypoxia, the circulatory system is challenged to facilitate oxygen delivery to working tissues through cerebral autoregulation which influences fatigue development and muscle performance. The aim of the study was to evaluate the effects of different levels of normobaric hypoxia on the changes in peripheral and cerebral oxygenation and performance during repeated sprints to exhaustion. Eleven recreationally active participants (six men and five women; 26.7 ± 4.2 years, 68.0 ± 14.0 kg, 172 ± 12 cm, 14.1 ± 4.7% body fat) completed three randomized testing visits in conditions of simulated altitude near sea-level (~380 m, FIO2 20.9%), ~2000 m (FIO2 16.5 ± 0.4%), and ~3800 m (FIO2 13.3 ± 0.4%). Each session began with a 12-min warm-up followed by two 10-s sprints and the repeated cycling sprint (10-s sprint: 20-s recovery) test to exhaustion. Measurements included power output, vastus lateralis, and prefrontal deoxygenation [near-infrared spectroscopy, delta (Δ) corresponds to the difference between maximal and minimal values], oxygen uptake, femoral artery blood flow (Doppler ultrasound), hemodynamic variables (transthoracic impedance), blood lactate concentration, and rating of perceived exertion. Performance (total work, kJ; −27.1 ± 25.8% at 2000 m, p < 0.01 and −49.4 ± 19.3% at 3800 m, p < 0.001) and pulse oxygen saturation (−7.5 ± 6.0%, p < 0.05 and −18.4 ± 5.3%, p < 0.001, respectively) decreased with hypoxia, when compared to 400 m. Muscle Δ hemoglobin difference ([Hbdiff]) and Δ tissue saturation index (TSI) were lower (p < 0.01) at 3800 m than at 2000 and 400 m, and lower Δ deoxyhemoglobin resulted at 3800 m compared with 2000 m. There were reduced changes in peripheral [Δ[Hbdiff], ΔTSI, Δ total hemoglobin ([tHb])] and greater changes in cerebral (Δ[Hbdiff], Δ[tHb]) oxygenation throughout the test to exhaustion (p < 0.05). Changes in cerebral deoxygenation were greater at 3800 m than at 2000 and 400 m (p < 0.01). This study confirms that performance in hypoxia is limited by continually decreasing oxygen saturation, even though exercise can be sustained despite maximal peripheral deoxygenation. There may be a cerebral autoregulation of increased perfusion accounting for the decreased arterial oxygen content and allowing for task continuation, as shown by the continued cerebral deoxygenation.

Effects of kinesio taping on anaerobic power recovery after eccentric exercise

ABSTRACTThe aim of the study was to evaluate the effectiveness of kinesio taping (KT) in anaerobic power recovery after eccentric exercise. The study was carried out on 10 healthy men. The participants performed two 60-min downhill runs with a constant intensity. Peak anaerobic power (PP) and mean power (MP) were measured before and five times after eccentric exercise. Anaerobic power was evaluated with the Maximal Cycling Sprint Test. After the downhill run, passive recovery (PR) and KT (lymphatic application) were applied in random order. A significant decrease in PP and MP was observed at least for 24 h after PR, compared to baseline. After the KT application 24 h after eccentric exercises, anaerobic power was already similar to the baseline measurement. The application of KT significantly improved anaerobic power recovery time after eccentric exercise compared to the period of passive rest immediately prior to testing.

Nitrate Intake Promotes Shift in Muscle Fiber Type Composition during Sprint Interval Training in Hypoxia.

Purpose: We investigated the effect of sprint interval training (SIT) in normoxia, vs. SIT in hypoxia alone or in conjunction with oral nitrate intake, on buffering capacity of homogenized muscle (βhm) and fiber type distribution, as well as on sprint and endurance performance.Methods: Twenty-seven moderately-trained participants were allocated to one of three experimental groups: SIT in normoxia (20.9% FiO2) + placebo (N), SIT in hypoxia (15% FiO2) + placebo (H), or SIT in hypoxia + nitrate supplementation (HN). All participated in 5 weeks of SIT on a cycle ergometer (30-s sprints interspersed by 4.5 min recovery-intervals, 3 weekly sessions, 4–6 sprints per session). Nitrate (6.45 mmol NaNO3) or placebo capsules were administered 3 h before each session. Before and after SIT participants performed an incremental VO2max-test, a 30-min simulated cycling time-trial, as well as a 30-s cycling sprint test. Muscle biopsies were taken from m. vastus lateralis.Results: SIT decreased the proportion of type IIx muscle fibers in all groups (P < 0.05). The relative number of type IIa fibers increased (P < 0.05) in HN (P < 0.05 vs. H), but not in the other groups. SIT had no significant effect on βhm. Compared with H, SIT tended to enhance 30-s sprint performance more in HN than in H (P = 0.085). VO2max and 30-min time-trial performance increased in all groups to a similar extent.Conclusion: SIT in hypoxia combined with nitrate supplementation increases the proportion of type IIa fibers in muscle, which may be associated with enhanced performance in short maximal exercise. Compared with normoxic training, hypoxic SIT does not alter βhm or endurance and sprinting exercise performance.