Time Trial Test Research Articles

Physical Exercise Program To Improve The Sport Performance On Speed Skating In Children

PURPOSE: To investigate the effects of physical exercise program on sport performance of children speed skaters. METHODS: A total of 52 children speed skaters (aged=9.09±0.27; 69.2% girls) from Ecuador participated in the study. The ALPHA-Fitness battery was used to analyze the body composition and physical fitness: muscular fitness (hand-grip strength and standing long jump test), speed-agility (4x10-m shuttle run test), and cardiovascular fitness (20-m shuttle run test). Sport performance was measured by the time-marks of the different modalities of the speed skating (combined test, time trial, sprint and hare test). All participants were evaluated before and after 10-weeks of intervention based on a physical exercise program (90-min/ session, 4-days/week). A mixed factorial ANOVA was used to analyze effects and interactions of the study factors age (<10-y and >10-y), sex (boys and girls), and measure moments (baseline and post-intervention) on body composition, physical fitness, and sport performance. RESULTS: Post-intervention compared with baseline, weight was lower in girls <10-yr (MD=0.66± 0.30 Kg, p=0.033), fat mass was lower in girls <10-yr and >10-yr (MD= 7.37±1.21 Kg, p<0.001; MD=7.71±1.71 Kg, p<0.001), muscle mass was lower in boys >10-yr (MD=0.13± 0.06 Kg, p<0.035) and bone mass was higher in girls <10-yr DM=0.28±0.09, p=0.03). The muscular fitness of upper limbs was higher post-intervention compared with baseline in boys <10-yr (DM=1.55± 0.57, p=0.010) and girls <10-yr (MD=1.58±0.35, p<0.01). For lower limbs, muscular fitness post-intervention was higher in girls <10-yr (MD=5.20± 2.28, p=0.02). The cardiovascular fitness was higher post-intervention in girls <10-yr (MD=0.65±0.20, p=0.002) compared with baseline. The time marks of the combined test post-intervention was lower in boys >10-yr (MD=6.06 ±2.00, p=0.004, in time trial the time-mark was lower in boys <10-yr (MD=0.71± 0.19, p=0.001), girls <10-yr (MD=0.52±0.12, p<0.001) and in girls >10-yr (MD=0.38±0.17 p=0.027) compared with baseline. The time-mark in sprint was lower for girls <10-yr (MD=2.39±1.02, p=0.023) post-intervention. CONCLUSION: A 10-weeks physical exercise intervention improves sport performance in children speed skaters, what are directly related with sex and age.

Endurance, aerobic high-intensity, and repeated sprint cycling performance is unaffected by normobaric "Live High-Train Low": a double-blind placebo-controlled cross-over study.

The aim was to investigate whether 6weeks of normobaric "Live High-Train Low" (LHTL) using altitude tents affect highly trained athletes incremental peak power, 26-km time-trial cycling performance, 3-min all-out performance, and 30-s repeated sprint ability. In a double-blinded, placebo-controlled cross-over design, seven highly trained triathletes were exposed to 6weeks of normobaric hypoxia (LHTL) and normoxia (placebo) for 8h/day. LHTL exposure consisted of 2 weeks at 2500m, 2weeks at 3000m, and 2weeks at 3500m. Power output during an incremental test, ~26-km time trial, 3-min all-out exercise, and 8 × 30s of all-out sprint was evaluated before and after the intervention. Following at least 8weeks of wash-out, the subjects crossed over and repeated the procedure. Incremental peak power output was similar after both interventions [LHTL: 375 ± 74 vs. 369 ± 70W (pre-vs-post), placebo: 385 ± 60 vs. 364 ± 79W (pre-vs-post)]. Likewise, mean power output was similar between treatments as well as before and after each intervention for time trial [LHTL: 257 ± 49 vs. 254 ± 54W (pre-vs-post), placebo: 267 ± 57 vs. 267 ± 52W (pre-vs-post)], and 3-min all-out [LHTL: 366 ± 68 vs. 369 ± 72W (pre-vs-post), placebo: 365 ± 66 vs. 355 ± 71W (pre-vs-post)]. Furthermore, peak- and mean power output during repeated sprint exercise was similar between groups at all time points (n = 5). In conclusion, 6weeks of normobaric LHTL using altitude tents simulating altitudes of 2500-3500m conducted in a double-blinded, placebo-controlled cross-over design do not affect power output during an incremental test, a ~26-km time-trial test, or 3-min all-out exercise in highly trained triathletes. Furthermore, 30s of repeated sprint ability was unaltered.

Influence of Inspiratory Muscle Training on Ventilatory Efficiency and Cycling Performance in Normoxia and Hypoxia.

The aim of this study was to analyse the influence of inspiratory muscle training (IMT) on ventilatory efficiency, in normoxia and hypoxia, and to investigate the relationship between ventilatory efficiency and cycling performance. Sixteen sport students (23.05 ± 4.7 years; 175.11 ± 7.1 cm; 67.0 ± 19.4 kg; 46.4 ± 8.7 ml·kg−1·min−1) were randomly assigned to an inspiratory muscle training group (IMTG) and a control group (CG). The IMTG performed two training sessions/day [30 inspiratory breaths, 50% peak inspiratory pressure (Pimax), 5 days/week, 6-weeks]. Before and after the training period subjects carried out an incremental exercise test to exhaustion with gas analysis, lung function testing, and a cycling time trial test in hypoxia and normoxia. Simulated hypoxia (FiO2 = 16.45%), significantly altered the ventilatory efficiency response in all subjects (p < 0.05). Pimax increased significantly in the IMTG whereas no changes occurred in the CG (time × group, p < 0.05). Within group analyses showed that the IMTG improved ventilatory efficiency (VE/VCO2 slope; EqCO2VT2) in hypoxia (p < 0.05) and cycling time trial performance [WTTmax (W); WTTmean (W); PTF(W)] (p < 0.05) in hypoxia and normoxia. Significant correlations were not found in hypoxia nor normoxia found between ventilatory efficiency parameters (VE/VCO2 slope; LEqCO2; EqCO2VT2) and time trial performance. On the contrary the oxygen uptake efficiency slope (OUES) was highly correlated with cycling time trial performance (r = 0.89; r = 0.82; p < 0.001) under both conditions. Even though no interaction effect was found, the within group analysis may suggest that IMT reduces the negative effects of hypoxia on ventilatory efficiency. In addition, the data suggest that OUES plays an important role in submaximal cycling performance.

Short term parasympathetic reactivation after the LSCT: a practical tool to predict and monitor cycling performance

Abstract Introduction: The measurement of heart rate recovery (HRR) and parasympathetic reactivation after exercise to predict and monitor changes in training status has gained popularity over the last few years (Daanen et al, 2012, Bellenger et al., 2016). More recently, short term parasympathetic reactivation (LnRMSSD) has gained popularity as a marker of training status. However it has not yet been established over which time frame short term LnRMSSD should be measured and if gender effects LnRMSSD measurement. Therefore the aim of this study was to determine the LnRMSSD time interval with the highest reliability, determine the relationship between LnRMSSD and cycling performance and, determine if LnRMSSD is similar in male cyclists  Methods: Fifty male (5.1±0.6 W/kg) and twenty female (4.8±0.3 W/kg) cyclists participated om the study. Both HRR and LnRMSSD were captured as part of the LSCT (Lamberts et al., 2014), which was used as a warm-up before a Peak Power Output (PPO) test (including VO2max determination), and two days later before aa 40km time trial (40km TT) test. The reliability of the measurement was determined over 6 LSCT’s, while 30, 60 and 90 second LnRMSSD data intervals were captured. Relationships were analysed between the most reliable LnRMSSD measurement and PPO, VO2max and 40km TT performance  Results: The reliability and associated typical error of the measurement (TEM) of the parasympathetic measurements were the lowest over the 60 second period (LnRMSSD60s) (ICC: 0.99; TEM: 7.7%). The relationship between HRR and training status was weaker than the relationship LnRMSSD60s and training status. Strong relationships were found between PPO & LnRMSSD60s in male (r = 0.93; p < 0.0001) and female (r = 0.85; p < 0.0001) cyclists. Slightly weaker relationships were found between VO2max & LnRMSSD60s in male (r = 0.71; p < 0.0001) and female (r = 0.63; p < 0.0001) cyclists and 40km TT time & LnRMSSD60s in male (r = -0.83; p < 0.0001) and female (r = -0.63; p = 0.003) cyclists. Although similar slopes were found in male and female cyclists, the y-axis intercept was significant different in all three performance parameters relationships with LnRMSSD60s (p < 0.0001).  Discussion: Short term parasympathetic reactivation after the LSCT is a promising new parameter that will assist in more accurately predict and monitor training status in cyclists. The most reliable LnRMSSD measurement was found over a 60s period (LnRMSSD60s). Good relationship between LnRMSSD60s and PPO, VO2max and 40km TT were found both in male and female cyclists. Although similar relationships were found in male and female cyclists, different y-axis intercept were found. This finding indicates that LnRMSSD60s values in female cyclists relate differently to training status than in male cyclists. Although this study used the relationship between LnRMSSD60S and cycling performance parameters (PPO, VO2max and 40km TT time), the author would like to emphasize that the actual LnRMSSD60s measurement should be used for monitoring purposes and not the predicted cycling performance values. In addition, the author would like to emphasize that a multi-factorial approach (e.g. power, cadence and RPE from the LSCT) should be used to predict, monitor, and fine tune training prescription in cycling.

Selected plantar pressure characteristics associated with the skating performance of national in-line speed skaters

In order to help coaches analyse the techniques of professional in-line speed skaters for making the required fine adjustments and corrections in their push-off work, this study analysed the specific plantar pressure characteristics during a 300-m time-trial test. Fourteen elite in-line speed skaters from the national team were recruited in this study. The total completion time of the 300-m time-trial test, duration of each skating phase, and plantar pressure distribution were measured. The correlation between plantar pressure distribution and skating performance was assessed using Pearson correlation analyses. The results showed that the contact time of the total foot and force–time integral (FTI) in the medial forefoot were significantly correlated with the duration of the start phase, and the FTIs in the medial forefoot of the gliding (left) leg and lateral forefoot of the pushing (right) leg were significantly correlated with the duration of the turning phase. The maximum force in the medial heel, medial forefoot, and median forefoot and the FTI in the medial heel and medial forefoot were significantly correlated with the duration of the linear acceleration phase. The results suggest that a correct plantar loading area and push-off strategy can enhance the skating performance.

Cardiorespiratory fitness and aerobic performance adaptations to a 4-week sprint interval training in young healthy untrained females

PurposeThe aim of this study was to test the effects of sprint interval training (SIT) on cardiorespiratory fitness and aerobic performance measures in young females.MethodsEight healthy, untrained females (age 21 ± 1 years; height 165 ± 5 cm; body mass 63 ± 6 kg) completed cycling peak oxygen uptake ( dot{V}{text{O}}_{2} peak), 10-km cycling time trial (TT) and critical power (CP) tests pre- and post-SIT. SIT protocol included 4 × 30-s “all-out” cycling efforts against 7 % body mass interspersed with 4 min of active recovery performed twice per week for 4 weeks (eight sessions in total).ResultsThere was no significant difference in dot{V}{text{O}}_{2} peak following SIT compared to the control period (control period: 31.7 ± 3.0 ml kg−1 min−1; post-SIT: 30.9 ± 4.5 ml kg−1 min−1; p > 0.05), but SIT significantly improved time to exhaustion (TTE) (control period: 710 ± 101 s; post-SIT: 798 ± 127 s; p = 0.00), 10-km cycling TT (control period: 1055 ± 129 s; post-SIT: 997 ± 110 s; p = 0.004) and CP (control period: 1.8 ± 0.3 W kg−1; post-SIT: 2.3 ± 0.6 W kg−1; p = 0.01).ConclusionsThese results demonstrate that young untrained females are responsive to SIT as measured by TTE, 10-km cycling TT and CP tests. However, eight sessions of SIT over 4 weeks are not enough to provide sufficient training stimulus to increase dot{V}{text{O}}_{2} peak.

No Improved Performance With Repeated-Sprint Training in Hypoxia Versus Normoxia: A Double-Blind and Crossover Study.

Few recent studies indicate that short-term repeated-sprint (RS) training in hypoxia (RSH) improves RS performance compared with identical training under normoxic conditions (RSN) in endurance-trained subjects. To determine the effects of RSH against RSN on RS performance under normoxic and moderate hypoxic conditions, using a randomized, doubleblind, crossover experimental design. Fifteen endurance-trained male subjects (age 25 ± 4 y) performed 4 wk of RS training (3 sessions/wk) in normobaric hypoxia (RSH, FiO2 = 13.8%) and normoxia (RSN, FiO2 = 20.9%) in a crossover manner. Before and after completion of training, RS tests were performed on a cycle ergometer with no prior exercise (RSNE), after an incremental exercise test (RSIE), and after a time-trial test (RSTT) in normoxia and hypoxia. Peak power outputs at the incremental exercise test and time-trial performance were unaltered by RSH in normoxia and hypoxia. RS performance was generally enhanced by RSH, as well as RSN, but there were no additional effects of RSH over RSN on peak and mean sprint power output and the number of repeated sprints performed in the RSNE, RSIE, and RSTT trials under normoxic and hypoxic conditions. The present double-blind crossover study indicates that RSH does not improve RS performance compared with RSN in normoxic and hypoxic conditions in endurance-trained subjects. Therefore, caution should be exercised when proposing RSH as an advantageous method to improve exercise performance.

Comparison of Rowing Performance Improvements Following Various High-Intensity Interval Trainings.

The purpose of this study was to examine the effects of high-intensity interval training (HIT) and supramaximal interval training (SMIT) on indoor rowing performance; 20 male lightweight collegiate rowers (age = 21.77 ± 2.35 years, height = 178.4 ± 6 cm, body mass = 69.6 ± 3.1 kg) participated in this study. Baseline testing involved a 2,000-m time trial and incremental exercise test to determine VO2peak, peak power output (PPO), and power at 4 mmol·L blood lactate threshold. After the baseline tests, participants were allocated to SMIT or HIT intervention groups, which they performed 8 times over a 4-week period (2 times per week, 2 days apart). The SMIT involved 10 × 30-second intervals at 150% of the PPO with 4-minute rest. The HIT involved 8 × 2.5-minute intervals at 90% of the PPO with 3-minute rest. Of note, 5.7 and 5 seconds of improvements were observed in 2,000-m performance after SMIT and HIT interventions, respectively. Of note, 2,000-m time trial performance, 2,000-m power, PPO, relative, and absolute VO2peak were significantly improved after both training interventions. However, the differences between the groups were not significant. As a result, 4 weeks of SMIT improves 2,000-m rowing ergometer performance and related physiological variables in a similar fashion with HIT in collegiate rowers.

Effects of Inhaled Oxygen Levels on Training Intensity and Subsequent Exercise Performance in Acute Hypoxia

In many cases, athletes and soldiers must travel to high-altitude environments without adequate time for pre-acclimation. Many may utilize intermittent hypoxia training as part of their normal conditioning program in an attempt to be better prepared for vigorous tasks at altitude. While prolonged exposure to hypoxia has been shown to increase hemoglobin mass, absolute training intensity is reduced in hypoxia and may lead to peripheral detraining. Training in hyperoxia has been shown to increased absolute training load and may improve training response. PURPOSE: We sought to compare the effects of 3 weeks of high intensity interval training in hypoxia or hyperoxia on exercise performance in acute hypoxia. METHODS: Sixteen aerobically trained males (20 ± 2 yr, 72.6 ± 9.8 kg, 49.4 ± 7.4 mL-1 • kg-1 • min-1) completed a progressive exercise test to exhaustion in normoxia (PIO2 = 142 Torr) to determine VO2 max and ventilatory threshold (VT). Subjects were then matched by fitness but otherwise randomly assigned to either a hypoxic (HYPO) or hyperoxic (HYPER) training group. Each then completed a pre-training time trial test (TT) of 2 kJ · kg bm-1 as fast as possible in hypoxia (PIO2 = 88 Torr). Subjects then underwent 3 wks of 3x/wk interval training in hypoxia (PIO2 = 88 Torr) (HYPO) or hyperoxia (PIO2 = 400 Torr) (HYPER). Training consisted of 6 x 0.48 kJ · kg bm-1 efforts per session performed as quickly as possible. After the training period, subjects completed a second hypoxic TT. All exercise was performed on an electronically braked ergometer. Training intensity relative to normoxic VT, SaO2 during training sessions, and percent improvement hypoxic TT completion time were used as dependent variables. Data were analyzed using independent t-tests. RESULTS: HYPER subjects trained at a significantly higher percentage of their normoxic VT power output (103 ± 10%) compared to HYPO (85 ± 9%) (P = 0.002) and maintained significantly higher SaO2 (100 ± 1% HYPER, 83 ± 3%, P<0.001) during training. Mean improvement for the TT was significantly greater in HYPER (12 ± 6%) vs HYPO (6 ± 5%) (P=0.047). CONCLUSION: The results suggest that in comparison to training in hypoxia, performing identical training in hyperoxia results in superior exercise performance in acute hypoxia.

Cardiovascular control, autonomic function, and elite endurance performance in spinal cord injury.

We aimed to determine the relationship between level of injury, completeness of injury, resting as well as exercise hemodynamics, and endurance performance in athletes with spinal cord injury (SCI). Twenty-three elite male paracycling athletes (C3-T8) were assessed for neurological level/completeness of injury, autonomic completeness of injury, resting cardiovascular function, and time to complete a 17.3-km World Championship time-trial test. A subset were also fitted with heart rate (HR) monitors and their cycles were fitted with a global positioning systems device (n = 15). Thoracic SCI exhibited higher seated systolic blood pressure along with superior time-trial performance compared with cervical SCI (all P < 0.01). When further stratified by autonomic completeness of injury, the four athletes with cervical autonomic incomplete SCI exhibited a faster time-trial time and a higher average speed compared with cervical autonomic complete SCI (all P < 0.042). Maximum and average HR also tended to be higher in cervical autonomic incomplete vs autonomic complete. There were no differences in time-trial time, HR, or speed between thoracic autonomic complete vs incomplete SCI. In conclusion, autonomic completeness of injury and the consequent ability of the cardiovascular system to respond to exercise appear to be a critical determinant of endurance performance in elite athletes with cervical SCI.

Concurrent Training in Elite Male Runners

Much recent attention has been given to the compatibility of combined aerobic and anaerobic training modalities. However, few of these studies have reported data related to well-trained runners, which is a potential limitation. Therefore, because of the limited evidence available for this population, the main aim was to determine which mode of concurrent strength-endurance training might be the most effective at improving running performance in highly trained runners. Eighteen well-trained male runners (age 23.7 ± 1.2 years) with a maximal oxygen consumption (VO2max) more than 65 ml·kg(-1)·min(-1) were randomly assigned into 1 of the 3 groups: Endurance-only Group (n = 6), who continued their usual training, which included general strength training with Thera-band latex-free exercise bands and endurance training; Strength Group (SG; n = 6) who performed combined resistance and plyometric exercises and endurance training; Endurance-SG (ESG; n = 6) who performed endurance-strength training with loads of 40% and endurance training. The study comprised 12 weeks of training in which runners trained 8 times a week (6 endurance and 2 strength sessions) and 5 weeks of detraining. The subjects were tested on 3 different occasions (countermovement jump height, hopping test average height, 1 repetition maximum, running economy (RE), VO2max, maximal heart rate [HRmax], peak velocity (PV), rating of perceived exertion, and 3-km time trial were measured). Findings revealed significant time × group interaction effects for almost all tests (p < 0.05). We can conclude that concurrent training for both SG and ESG groups led to improved maximal strength, RE, and PV with no significant effects on the VO2 kinetics pattern. The SG group also seems to show improvements in 3-km time trial tests.

Physiological Determinants of the Cycling Time Trial

The purpose of this study was to examine the physiological determinants of endurance cycling time trial (TT) performance in a heterogeneous group of competitive male road cyclists. About 15 male cyclists who had all competed in cycling the preceding season were tested for the anthropometric variables height, body weight, leg length, ankle circumference, and body fat percentage. They were also tested for maximal oxygen consumption (VO2max), lactate threshold (LT), metabolic cost of cycling (CC), peak power output and average power output during a 30-second Wingate test, 1 repetition maximum and peak power in half squats, and a TT test on an ergometer. Heart rate and cadence (rounds per minute, RPM) were continuously measured during all cycle tests. Pearson Bivariate correlation tests and single linear regression tests were performed to obtain correlation coefficients (r), effect size (F), standard error of estimate (SEE), and 95% confidence interval. The single variable that correlated best with TT performance was power output at LT (r = 0.86, p < 0.01). Standard error of estimate was 7.5%. Lactate threshold expressed in %VO2max did not correlate significantly with TT performance. An equation representing both aerobic and anaerobic endurance capacity TT(w) = 0.95 ([VO2max/CC] TT%VO2max) + 0.05 (Wingate average) correlated strongly with TT laboratory performance (r = 0.93, p < 0.01, SEE = 5.7%). None of the strength, power, or anthropometric variables correlated significantly with TT laboratory performance.

Therapeutic use of coconut water

This paper is a review about therapeutic use of coconut water. We began with its chemical composition, pointing that it is reach in antioxidants, potassium, calcium, carbohydrates, and poor in sodium. The antioxidant activity from coconut water is of interest as a potential natural food antioxidant additive, a nutraceutical. When coconut water is used in hypertensive people, this brought about a large decrease in blood pressure, including increased frequency in urination suggest a possible diuretic action. Additionally, in all cases of persons consuming coconut water on a regular basis an increase in the plasma level of potassium is observed. This would be a contributing factor in the decreases in blood pressure, suggesting a potassium sparing natriuretic. Some time trial tests as the measure of exercise performance have determined the efficacy of coconut water and other beverages on enhancing hydration and performance following dehydrating exercise. In conclusion, coconut water can be used in cases of hypertension, rehydration in sports, together with early refeeding, as a home glucose electrolyte oral rehydration solution in the early stages of mild diarrhoeal disease, despite not having a balanced electrolyte composition. However, it should not be used in patients with severe diarrhoea, or in patients who are severely dehydrated and/or in whom renal function is impaired. Further studies should be conducted to better understand the effects of coconut water as a therapeutic agent.

The study of CELL FOOD improve cyclist aerobic endurance

To investigate how CELL FOOD improve the cyclist performance.METHODSPart I: 10 cyclists were divided two groups randomly, CF (cell food) group and PL (placebo) group. CF group used 30 drops per time with pure water, 3 times per day without other nutritional supplements for 28 days constant. PL group used mimetic acidic water and the dose was the same. At week 0 and week 4, all subjects do graded exercises test and at week 2 and week 3, do 3 km individual time trial test at track. Part II: 11 cyclists from different team. At day 0, without cell food; at day 1, before, during and after training, all subjects drink 30 drops separately; at day 2, only after training, all subjects drink 30 drops. Part I's results show that: 1) Compare week 0 with week 4, MaxVO2, peak power, and power at 4 mmol/l lactate acid were be improved. At week 4, the same trend can be found. 2) The competition result and heart rate 2 minutes after competition of CF group are better than PL group, P &lt;0.05. Part II result indicated that: Three parameters like live support energy, oxygen intake rate, single load time at day 1 and day 2 are better than day 0, P&lt;0.05. CF can improve aerobic endurance by change the oxygen intake, oxygen utilization, power output of cyclist.

Time Trials Predict the Competitive Performance Capacity of Junior Cross-Country Skiers

This study investigated whether there is a correlation between time-trial performance and competitive performance capacity of male and female junior cross-country skiers and sought to explain sex-specific competitive performance capacity through multiple-regression modeling. The International Ski Federation's (FIS) junior ranking points for distance (FISdist) and sprint (FISsprint) competitions were used as performance parameters. A total of 38 elite junior (age 18.5 ± 1.0 y) cross-country skiers (24 men and 14 women) completed 3 time-trial tests: a 3-km level-running time trial (TTRun), a 2-km moderate uphill (1.2° slope) roller-skiing time trial using the double-poling technique (TTDP), and a 2-km uphill (2.8° slope) roller-skiing time trial using the diagonal-stride technique (TTDiag). The correlations were investigated using Pearson correlation analysis, and regression models were created using multiple-linear-regression analysis. For men, FISsprint and FISdist were correlated with the times for TTRun, TTDP, and TTDiag (all P < .001). For women, FISsprint was correlated with the times for TTRun (P < .05), TTDP (P < .01), and TTDiag (P < .01), whereas FISdist was correlated only with the times for TTDP (P < .01) and TTDiag (P < .05). The models developed for FISdist and FISsprint explained 73.9-82.3% of the variance in the performance capacity of male junior cross-country skiers. No statistically valid regression model was found for the women. Running and roller-skiing time trials are useful tests for accurately predicting the performance capacity of junior cross-country skiers.

Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men

BackgroundSport drinks are ubiquitous within the recreational and competitive fitness and sporting world. Most are manufactured and artificially flavored carbohydrate-electrolyte beverages. Recently, attention has been given to coconut water, a natural alternative to manufactured sport drinks, with initial evidence indicating efficacy with regard to maintaining hydration. We compared coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men.MethodsFollowing a 60-minute bout of dehydrating treadmill exercise, 12 exercise-trained men (26.6 ± 5.7 yrs) received bottled water (BW), pure coconut water (VitaCoco®: CW), coconut water from concentrate (CWC), or a carbohydrate-electrolyte sport drink (SD) [a fluid amount based on body mass loss during the dehydrating exercise] on four occasions (separated by at least 5 days) in a random order, single blind (subject and not investigators), cross-over design. Hydration status (body mass, fluid retention, plasma osmolality, urine specific gravity) and performance (treadmill time to exhaustion; assessed after rehydration) were determined during the recovery period. Subjective measures of thirst, bloatedness, refreshed, stomach upset, and tiredness were also determined using a 5-point visual analog scale.ResultsSubjects lost approximately 1.7 kg (~2% of body mass) during the dehydrating exercise and regained this amount in a relatively similar manner following consumption of all conditions. No differences were noted between coconut water (CW or CWC) and SD for any measures of fluid retention (p > 0.05). Regarding exercise performance, no significant difference (p > 0.05) was noted between BW (11.9 ± 5.9 min), CW (12.3 ± 5.8 min), CWC (11.9 ± 6.0 min), and SD (12.8 ± 4.9 min). In general, subjects reported feeling more bloated and experienced greater stomach upset with the CW and CWC conditions.ConclusionAll tested beverages are capable of promoting rehydration and supporting subsequent exercise. Little difference is noted between the four tested conditions with regard to markers of hydration or exercise performance in a sample of young, healthy men. Additional study inclusive of a more demanding dehydration protocol, as well as a time trial test as the measure of exercise performance, may more specifically determine the efficacy of these beverages on enhancing hydration and performance following dehydrating exercise.

Fatigue level after maximal exercise test (laboratory and road) in cyclists

Cordova A, Sainz J, Cuervas-Mons M, Tur JA, Pons A. Fatigue level after maximal exercise test (laboratory and road) in cyclists. J. Hum. Sport Exerc. Vol. 5, No. 3, pp. 358-369, 2010. Despite the importance of uphill cycling performance during cycling competitions, there is very little research investigating uphill cycling, particularly concerning field studies. The lack of research is partly due to the difficulties in obtaining data in the field. The aim of this study was analyze the fatigue after a maximal exercise test and the maximal blood lactate in elite cyclists after two maximal exercises, one on laboratory and other in field. In this study 14 semi-professional cyclists have participated. The trials consisted in a laboratory incremental test (LIT) to exhaustion, and a maximal individual uphill time trial test on road (UTT) (5.85±0.24% slope) during 12-minute. The results showed that in LIT the maximal heart rate (HRmax) (beats·min -1 ) was 188±9.8, with a maximum of blood lactate (LAmax) (mmol·L -1 ) of 13.9±2.5. Similar data were obtained in the 12 min maximal UTT (LAmax 15.2±3.1 mmol·L -1 , and HRmax 188±6.5 beats·min -1 ). A high correlation of LAmax (0.70) and HRmax (0.86) was obtained from both trials. No differences were observed with respect the fatigue data (psychological and dynamometric) between both test LIT vs UTT.We conclude that UTT test on road as a useful test to evaluate the cyclist’s physical condition. We think that is perfectly valid, reliable and reproducible, and is possible to carried by the made for the own cyclist or for the trainers. On the other hand, is important because we can obtain information about of performance as well as power feeling of cyclist. These results may be significant in physiological terms to monitor the training and for

Measuring submaximal performance parameters to monitor fatigue and predict cycling performance: a case study of a world-class cyclo-cross cyclist

Recently a novel submaximal test, known as the Lamberts and Lambert submaximal cycle test (LSCT), has been developed with the purpose of monitoring and predicting changes in cycling performance. Although this test has been shown to be reliable and able to predict cycling performance, it is not known whether it can measure changes in training status. Therefore, the aim of this study was to determine whether the LSCT is able to track changes in performance parameters, and objective and subjective markers of well-being. A world class cyclo-cross athlete (31 years) volunteered to participate in a 10-week observational study. Before and after the study, a peak power output (PPO) test with respiratory gas analysis (VO(2max)) and a 40-km time trial (40-km TT) test were performed. Training data were recorded in a training logbook with a daily assessment of well-being, while a weekly LSCT was performed. After the training period all performance parameters had improved by a meaningful amount (PPO +5.2%; 40-km TT time -2.5%; VO(2max) +1.4%). Increased training loads during weeks 2 and 6 and the subsequent training-induced fatigue was reflected in the increased well-being scores. Changes during the LSCT were most clearly notable in (1) increased power during the first minute of third stage, (2) increased rating of perceived exertion during second and third stages, and (3) a faster heart rate recovery after the third stage. In conclusion, these data suggest that the LSCT is able to track changes in training status and detect the consequences of sharp increases in training loads which seem to be associated with accumulating fatigue.

Effects of High-Intensity Training by Heart Rate or Power in Well-Trained Cyclists

The aim of this study was to determine whether the performance of cyclists after 4 weeks of high-intensity training improved similarly using either heart rate or power to prescribe training. Twenty-one well-trained men cyclists (age, 32 +/- 6 years; peak power output, 371 +/- 46 W) were randomly assigned to a power-based (GPOWER) or heart rate-based (GHEART) high-intensity training (HIT) group or a control group (GCONTROL). Training consisted of 8 repetitions of 4 minutes at either 80% of peak power output (GPOWER) or at the heart rate coinciding with 80% of peak power output (GHEART), with rest periods of 90 seconds. A 40-km time trial and VO2max test were performed before and after 8 training sessions. There were significant improvements (p < 0.05) in peak power output (GPOWER = 3.5%; GHEART = 5.0%) and 40-km time trial performance (GPOWER = 2.3%; GHEART = 2.1%) for both of the high-intensity groups. Although there were no significant differences between groups for these variables, when the data were analyzed using magnitude-based effects, the GHEART group showed greater probability of a "beneficial" effect for peak power output. The current general perception that prescribing training based only on power is more effective than prescribing training based on heart rate was not supported by the data from this study. Coaches who are unable to monitor progress frequently should prescribe training based on heart rate, when intervals are performed under stable conditions, because this may provide an additional advantage over prescribing training using power.

Effect of Caffeine on Sport-Specific Endurance Performance: A Systematic Review

Endurance athletes often ingest caffeine because of its reported ergogenic properties. Although there are a vast number of studies quantifying caffeine's effects, many research studies measure endurance performance using a time-to-exhaustion test (subjects exercise at a fixed intensity to volitional exhaustion). Time-to-exhaustion as a performance measure is not ideal because of the high degree of measurement variability between and within subjects. Also, we are unaware of any endurance sports in which individuals win by going a longer distance or for a longer amount of time than their competitors. Measuring performance with a time-trial test (set distance or time with best effort) has high reproducibility and is more applicable to sport. Therefore, the purpose of this review was to critically and objectively evaluate studies that have examined the effect of caffeine on time-trial endurance (>5 minutes) performance. A literature search revealed 21 studies with a total of 33 identifiable caffeine treatments that measured endurance performance with a time-trial component. Each study was objectively analyzed with the Physiotherapy Evidence Database (PEDro) scale. The mean PEDro rating was 9.3 out of 10, indicating a high quality of research in this topic area. The mean improvement in performance with caffeine ingestion was 3.2 +/- 4.3%; however, this improvement was highly variable between studies (-0.3 to 17.3%). The high degree of variability may be dependent on a number of factors including ingestion timing, ingestion mode/vehicle, and subject habituation. Further research should seek to identify individual factors that mediate the large range of improvements observed with caffeine ingestion. In conclusion, caffeine ingestion can be an effective ergogenic aid for endurance athletes when taken before and/or during exercise in moderate quantities (3-6 mg.kg body mass). Abstaining from caffeine at least 7 days before use will give the greatest chance of optimizing the ergogenic effect.