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Use of muscle oxygen saturation (SmO2) has been validated as a performance factor during incremental exercise with portable near-infrared stereoscopy (NIRS) technology. However, there is little knowledge about the use of SmO2 to identify training zones. The objective of this study was to evaluate the metabolic zones by SmO2: maximum lipid oxidation zone (Fatmax), ventilatory thresholds (VT1 and VT2) and maximum aerobic power (MAP) during a graded exercise test (GXT). Forty trained cyclists and triathletes performed a GXT. Output power (W), heart rate (HR), oxygen consumption (VO2), energy expenditure (kcal/min) and SmO2 were measured. Data were analysed using the ANOVA test, ROC curves and multiple linear regressions. Significance was established at p ≤ 0.05. SmO2 decreases were observed from baseline (LB) to Fatmax (Δ = -16% p < 0.05), Fatmax to VT1 (Δ = -16% p < 0.05) and VT1 to VT2 (Δ = -45% p < 0.01). Furthermore, SmO2 together with weight, HR and output power have the ability to predict VO2 and energy expenditure by 89% and 90%, respectively. We conclude that VO2 and energy expenditure values can be approximated using SmO2 together with other physiological parameters and SmO2 measurements can be a complementary parameter to discriminate aerobic workload and anaerobic workload in athletes. [ABSTRACT FROM AUTHOR]

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Background. Metabolic stress is considered a key factor in the activation of hypertrophy mechanisms which seems to be potentiated under hypoxic conditions. This study aimed to analyze the combined effect of the type of acute hypoxia (terrestrial vs simulated) and of the inter-set rest configuration (60 vs 120 s) during a hypertrophic resistance training (RT) session on physiological, perceptual and muscle performance markers. Methods. Sixteen active men were randomized into two groups based on the type of hypoxia (hypobaric hypoxia, HH: 2,320 m asl; vs normobaric hypoxia, NH: FiO2 of 15.9%). Each participant completed in a randomly counterbalanced order the same RT session in four separated occasions: two under normoxia and two under the corresponding hypoxia condition at each prescribed inter-set rest period. Volume-load (load x set x repetition) was calculated for each training session. Muscle oxygenation (SmO2) of the vastus lateralis was quantified during the back squat exercise. Heart rate (HR) was monitored during training and over the ensuing 30-min post-exercise period. Maximal blood lactate concentration (maxLac) and rating of perceived exertion (RPE) were determined after the exercise and at the end of the recovery period. Results. Volume-load achieved was similar in all environmental conditions and interset rest period length did not appreciably affect it. Shorter inter-set rest periods displayed moderate increases in maxLac, HR and RPE responses in all conditions. Compared to HH, NH showed a moderate reduction in the inter-set rest-HR (ES > 0.80), maxLac (ES > 1.01) and SmO2 (ES > 0.79) at both rest intervals. Conclusions. Results suggest that the reduction in inter-set rest intervals from 120 s to 60 s provide a more potent perceptual, cardiovascular and metabolic stimulus in all environmental conditions, which could maximize hypertrophic adaptations in longer periods of training. The abrupt exposure to a reduced FiO2 at NH seems to reduce the inter-set recovery capacity during a traditional hypertrophy RT session, at least during a single acute exposition. These results cannot be extrapolated to longer training periods. [ABSTRACT FROM AUTHOR]

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Hydrogen-rich water (HRW) is used as a supplement to improve performance and reduce fatigue in athletes. However, the potentially beneficial effects of HRW intake could be mediated by the training status of athletes. The purpose of the study was to analyse the ergogenic effect of intake of HRW for one week on aerobic and anaerobic performance, both in trained and untrained individuals. Thirty-seven volunteers participated in the study and were divided into two experimental groups: trained cyclists and untrained subjects. A double-blind crossover design was performed in which all subjects took a placebo (PW) and nano-bubble HRW (pH: 7.5; hydrogen concentration: 1.9 ppm; oxidation-reduction potential (ORP): -600 mV). At the end of 7-day intake, performance was assessed by an incremental VO2max test and by a maximum anaerobic test. After HRW intake, only trained cyclists improved their performance in the anaerobic test with an increase in peak power (from 766.2 ± 125.6 to 826.5 ± 143.4 W; d = .51) and mean power (from 350.0 ± 53.5 to 380.2 ± 71.3 W; d = .51), and a decrease in the fatigue index (from 77.6 ± 5.8 to 75.1 ± 5.9%; d = .45). The findings demonstrate that the ergogenic effect of HRW is mediated by the training status, and that 7-day intake of HRW would be an effective strategy for improving anaerobic performance in trained cyclists. [ABSTRACT FROM AUTHOR]

Passive and active hypoxia could be used as a tool during a transitional phase to maintain the effects of warm-up and optimize athletic performance. Our purpose was to evaluate and compare the effects of four different re-warm-up strategies, i.e. rest in normoxia (RN) at FiO2 = 20.9%, rest in hypoxia (RH) at FiO2 = 15%, active (5 minutes dryland-based exercise circuit) in normoxia (AN) and active in hypoxia (AH), during the transitional phase, on subsequent 100 m maximal swimming performance. Thirteen competitive swimmers (n = 7 males; n = 6 females; age: 15.1±2.1 years; height: 164.7±8.8 cm; weight: 58.1±9.7 kg; 100 m season's best time 72.0±11.8 s) completed a 20-minute standardized in-water warm-up followed by a 30-minute randomized transitional phase and 100 m freestyle time trial. Compared to AH (73.4±6.2 s), 100 m swim time trials were significantly (p = 0.002; η2 = 0.766) slower in RN (75.7±6.7 s; p = 0.01), AN (75.2±6.7 s; p = 0.038) and RH (75.0±6.4 s; p = 0.009). Moreover, compared to AH (36.3±0.4ºC), tympanic temperature was significantly lower (p<0.001; η² = 0.828) at the end of the transitional phase in passive conditions (RN: 35.9±0.6; p = 0.032; RH: 36.0±0.4; p = 0.05). In addition, countermovement jump height at the end of the transitional phase was significantly higher in active than in passive conditions (p = 0.001; η² = 0.728). A dryland-based circuit under hypoxia could be useful to swimmers, once it has attenuated the decline in tympanic temperature during a 30-minute transitional phase after warm-up, improving 100 m swimming performance in young amateur swimmers. [ABSTRACT FROM AUTHOR]

The Ironman triathlon consists of a 3.8 km swim, 180 km bike, and 42.195 km run. Thermoregulation responses play an important role in performance optimization and injury prevention. Factors such as environmental conditions including heat and humidity, athlete training level, and race duration can affect thermoregulation. Hyperthermia occurs when the core temperature rises above 38.5°C. The present study aims to describe core temperature (Tcore) in top-level and well-trained age group triathletes during the marathon of Ironman World Championship 2014 in Kona-Hawaii under thermal stress conditions. Tcore of 15 triathletes (age: 36.11 ± 7.36 years, body mass: 71.14 ± 7.12 kg, height: 179 ± 0.04 cm, and fat %: 8.48 ± 0.85) who classified for the Ironman World Championship was measured by an ingestible pill telemetry system prior to competition, during the marathon and 60 min after finishing the race. Mean wet bulb globe temperature (WBGT) during the marathon was 24.66°C (range 22.44–28.50°C). Body mass index (BMI) and perceived exertion (Borg Scale and Visual Analog Scale-Pain) were collected before the race and 60 min after the event. Time variables were extracted from their official race time and split times. Finish time was 10: 06:56 ± 0:48:30. Tcore was initially 36.62 ± 0.17°C, increased at the end of the event (38.55 ± 0.64; p < 0.01) and remained elevated 60 min after the event (38.65 ± 0.41°C; p < 0.002). BMI significantly decreased after the event (22.85 ± 1.11 vs. 21.73 ± 1.36; p < 0.05), whereas both exercise perceived exertion [Borg Scale (10.2 ± 1.64 vs. 18.60 ± 1.67; p < 0.003)] and perceived muscle pain [VAS Pain (2.75 ± 1.59 vs. 9.08 ± 1.13; p < 0.001)] increased significantly after the event. Tcore during competition correlated negatively with position in age group (r − 0.949, p = 0.051), but not with race time (r = −0.817; p = 0.183). High-level age group triathletes competing under thermal stress conditions in the Kona Ironman reached a state of hyperthermia during the marathon. After 60 min of recovery the hyperthermia persisted. Strategies to aid post-event cooling and recovery should be considered to avoid the potentially dangerous adverse health effects of hyperthermia. [ABSTRACT FROM AUTHOR]

Hypoxic training methods are increasingly being used by researchers in an attempt to improve performance in normoxic ambients. Moreover, previous research suggests that resistance training in hypoxia can cause physiological and muscle adaptations. The primary aim of this study was to compare the effects of 8 weeks of high-intensity resistance circuit-based (HRC) training in hypoxia on body composition and strength performance. The secondary aim was to examine the effects of HRC on metabolic parameters. Twenty-eight male participants were randomly assigned to either hypoxia (Fraction of inspired oxygen [FIO2] = 15%; HRChyp: n = 15; age: 24.6 ± 6.8 years; height: 177.4 ± 5.9 cm; weight: 74.9 ± 11.5 kg) or normoxia [FIO2] = 20.9%; HRCnorm: n = 13; age: 23.2 ± 5.2 years; height: 173.4 ± 6.2 cm; weight: 69.4 ± 7.4 kg) groups. Training sessions consisted of two blocks of three exercises (Block 1: bench press, leg extension and front pull down; Block 2: deadlift, elbow flexion and ankle extension). Each exercise was performed at six repetition maximum. Rest periods lasted for 35-s between exercises, 3-min between sets and 5-min between blocks. Participants exercised twice weekly for 8 weeks, and body composition, strength and blood tests were performed before and after the training program. Lean body mass and bone mineral density significantly increased over time in the HRChyp (p <.005; ES = 0.14 and p <.014; ES = 0.19, respectively) but not in the HRCnorm after training. Both groups improved their strength performance over time (p <.001), but without group effect differences. These results indicate that simulated hypoxia during HRC exercise produced trivial effects on lean body mass and bone mineral density compared to normoxia. [ABSTRACT FROM AUTHOR]

Copyright of E-balonmano.com: Journal of Sports Science / Revista de Ciencias del Deporte is the property of Federacion Extremena de Balonmano and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Compare the effect of two protocols cold water immersion on indicators of recovery in female handball players. Methods: 12 female handball players (Age: 14 ± 0.7 years, body mass: 58.44 ± 7.8 kg, Height: 161± 7.1 cm, fat %: 21.5± 3) were involved in a "cross-over" experimental design. After three training sessions (Avg heart rate 183 ± 9, 180 ± 8 and 180 ± 8b/pm respectively), participants were placed a continuous cold water immersion protocol (n=12), (12 min water temperature 14± 0.5C°), intermittent cold water immersion protocol (n=11), (4 x 2 min water temperature 14 ± 0.5C° + 1min out of water ) and control group (CG) with passive recovery (n=9). Countermovement jump test (CMJ), Visual Analog Scale (VAS-Pain) and thigh volume were measured. Results: Both cold water immersion protocols were effective in reducing the pain immediately post immersion, 24 and 48 hours after training compared with the CG (F (4,116) = 6.84, p < 0.001. ωp²: 0.32). CMJ (F(4,116) = 1,79, p =.11, ωp²: 0.02) and thigh volume (F (4,116) = 0.77, p =.59, ωp²: -0.007) did not report statistically significant changes at any time of measurement. Conclusions: Both CWI protocols are effective to reduce delayed on set muscle soreness at all times post training in female handball players. CWI should be included after training sessions to enhance players' recovery for the next training day. CWI protocol could be used according to individual preferences due to both of them have same effect in psychological indicators of recovery. [ABSTRACT FROM AUTHOR]

Objectives: The main objective of this study was to compare two cold water immersion protocols, continuous or intermittent, on recovery in basketball players. Methods: Ten male basketball players (age: 14 ± 0.4 years, body mass: 65.4 ± 9.1 kg, height: 175 ± 7.3 cm, body fat %: 10.3 ± 4) were included in the study. After three 90-minute training sessions (avg. heart rate 158 ± 11.92, 156 ± 7.06 and 151 ± 10.44 bpm), participants were grouped into a continuous immersion (12 min at 12 ± 0.4°C) group, intermittent immersion (4 x 2 min immersion at 12 ± 0.4 °C + 1 min out of water) group and a control group (CG). Countermovement jump (CMJ), muscle pain and thigh volume were measured. Results: Both cold water immersion protocols were effective in reducing the pain 24 and 48 hours after training compared with the CG (F(3.54) = 2.91,p = 0.016, ηp2 = .24). Concerning CMJ change, % differences occurred at 24 (Z = 11.04,p = 0.004) and 48 hours (Z = 14.01,p < 0.001) in comparison with the CG. Regarding the muscle volume, the statistical analysis did not report a significant interaction (F(3.54) = 2.42,p = 0.058). Conclusion: Both cold water immersion CWI protocols are effective in improving recovery in basketball players. [ABSTRACT FROM AUTHOR]