Evidence to Practice: Bridging the Gap in Environmental Challenges (Cold, Heat, Hypoxia) in Sport and Exercise: Acclimatization/Acclimation, Training, Competitions, Recovery, Rehabilitation and Therapeutic Interventions

Editorial

17 November 2022

Editorial: Evidence to practice: Bridging the gap in environmental challenges (cold, heat, hypoxia) in sport and exercise: Acclimatization/acclimation, training, competitions, recovery, rehabilitation and therapeutic interventions

Franck Brocherie

Joao Brito

Julio A. Costa

and

Gregoire P. Millet

4,751 views

0 citations

Editors

Franck Brocherie

Institut national du sport, de l'expertise et de la performance (INSEP)

Gregoire P Millet

Université de Lausanne

João Brito

Portugal Football School, Portuguese Football Federation

Júlio A. Costa

Portugal Football School, Portuguese Football Federation

Impact

Mean core (A) and skin (B) temperature at different body parts before, during and after exercise. Dashed lines mark the start and end of the skiing bout.

Brief Research Report

02 November 2022

Effect of cold ambient temperature on heat flux, skin temperature, and thermal sensation at different body parts in elite biathletes

Thomas Blokker

, 2 more and

Jon Peter Wehrlin

2,260 views

2 citations

Heart rate changes at different time points for control (CON), lower-limb cold-water immersion condition (LCWI) and whole-body cold-water immersion condition (WCWI) conditions. t-test, agility t-test. 20 m, 20 m sprint test. Yo-Yo IE1, Yo-Yo intermittent endurance test level 1. The values are showed as mean ± SD.

Original Research

10 October 2022

Effect of 3 min whole-body and lower limb cold water immersion on subsequent performance of agility, sprint, and intermittent endurance exercise

Wei Zhang

, 1 more and

Xinyan Zheng

2,208 views

1 citations

Schematic representation of the experimental design.

Original Research

12 August 2022

Modulation of neuromuscular excitability in response to acute noxious heat exposure has no additional effects on central and peripheral fatigability

Nerijus Eimantas

, 3 more and

Marius Brazaitis

2,665 views

5 citations

Original Research

22 June 2022

A Heart Rate Based Algorithm to Estimate Core Temperature Responses in Elite Athletes Exercising in the Heat

Johannus Q. de Korte

, 5 more and

Thijs M. H. Eijsvogels

Purpose: Non-invasive non-obtrusive continuous and real-time monitoring of core temperature (T_c) may enhance pacing strategies, the efficacy of heat mitigation measures, and early identification of athletes at risk for heat-related disorders. The Estimated Core Temperature (ECTemp™) algorithm uses sequential heart rate (HR) values to predict T_c. We examined the validity of ECTemp™ among elite athletes exercising in the heat.

Methods: 101 elite athletes performed an exercise test in simulated hot and humid environmental conditions (ambient temperature: 31.6 ± 1.0°C, relative humidity: 74 ± 5%). T_c was continuously measured using a validated ingestible telemetric temperature capsule system. In addition, HR was continuously measured and used to compute the estimated core temperature (T_c−est) using the ECTemp™ algorithm.

Results: Athletes exercised for 44 ± 10 min and n = 5,025 readouts of T_c (range: 35.8–40.4°C), HR (range: 45–207 bpm), and T_c−est (range: 36.7–39.9°C) were collected. T_c−est demonstrated a small yet significant bias of 0.15 ± 0.29°C (p < 0.001) compared to T_c, with a limit of agreement of ±0.45°C and a root mean square error of 0.35 ± 0.18°C. Utilizing the ECTemp™ algorithm as a diagnostic test resulted in a fair to excellent sensitivity (73–96%) and specificity (72–93%) for T_c−est thresholds between 37.75 and 38.75°C, but a low to very-low sensitivity (50–0%) for T_c−est thresholds >39.0°C, due to a high prevalence of false-negative observations.

Conclusion: ECTemp™ provides a valuable and representative indication of thermal strain in the low- to mid-range of T_c values observed during exercise in the heat. It may, therefore, be a useful non-invasive and non-obtrusive tool to inform athletes and coaches about the estimated core temperature during controlled hyperthermia heat acclimation protocols. However, the ECTemp™ algorithm, in its current form, should not solely be used to identify athletes at risk for heat-related disorders due to low sensitivity and high false-negative rate in the upper end of the T_c spectrum.

4,496 views

4 citations

Changes in VEGF levels after Sirt3 inhibition and hypoxic training interventions. (× 400). Scale bars indicate 20 μm. C, control; HT, hypoxic training; 3-TYP, Sirt3 inhibitor 3-TYP; 3-TYP + HT, 3-TYP + hypoxic training. **p < 0.01 vs. C; ##p < 0.01 vs. HT; and p < 0.05 vs. 3-TYP. The results were presented as mean ± SEM.

Original Research

18 July 2022

Hypoxic Training Ameliorates Skeletal Muscle Microcirculation Vascular Function in a Sirt3-Dependent Manner

Chunwei Ma

, 2 more and

Binghong Gao

2,232 views

4 citations

Summary of design for training study with 4 sessions performed weekly. WBC, whole body cryotherapy; CON, control; 3RM, 3 repetition maximum; CMJ, countermovement jump test. *Weight for barbell squat progressed from 70% 1RM to 75% 1RM after 3 weeks.

Original Research

25 March 2022

The Effect of Repetitive Whole Body Cryotherapy Treatment on Adaptations to a Strength and Endurance Training Programme in Physically Active Males

Adnan Haq

, 2 more and

Anthony W. Baross

10,775 views

5 citations

Mean ± SD (A) arterial oxygen saturation (SpO2work); (B) relative heart rate (HRwork); (C) blood lactate concentration [La−]work; and median ± IQR (D) rating of perceived exertion (RPEwork) during the 5-min submaximal cycling test at baseline (i.e., near sea level) and on three weekly occasions during the training camp (i.e., at 1,800 m). Red circles, women; blue circles, men. *Significantly different from baseline (p < 0.05).

Original Research

11 May 2022

Monitoring Acclimatization and Training Responses Over 17–21 Days at 1,800 m in Elite Cross-Country Skiers and Biathletes

Øyvind Karlsson

, 1 more and

Kerry McGawley

3,228 views

5 citations

The effects of 4-weeks training in the 80%∆ intensity and time sustained of the Tlim test (A,B) and on the CP and W′ of the 3AOT (C,D) presented as mean (columns) and individual values (lines) in both pre- (gray) and post-intervention (white) periods following high-intensity exercise training sessions performed in hypoxia with NO3− (HNO), in hypoxia with placebo (HPL) and in normoxia with placebo (CON). Mean corresponding effect size (post-intervention mean—pre-intervention mean/square root of the sum of the two standard deviations minus 2*correlation coefficient) for HNO (black), HPL (gray), and CON (white) groups in both Tlim and 3AOT-related parameters are presented in (E). Threshold values considered for effect size were “trivial” (<0.2), “small” (0.2–0.6), “moderate” (0.6–1.2), and “large” (1.2–2.0). *Differences between pre- and post-intervention period (p < 0.05).

Original Research

14 March 2022

Dietary Nitrate Supplementation Is Not Helpful for Endurance Performance at Simulated Altitude Even When Combined With Intermittent Normobaric Hypoxic Training

Ana Sousa

, 3 more and

Grégoire P. Millet

Introduction: Training intensity and nutrition may influence adaptations to training performed in hypoxia and consequently performance outcomes at altitude. This study investigates if performance at simulated altitude is improved to a larger extent when high-intensity interval training is performed in normobaric hypoxia and if this is potentiated when combined with chronic dietary nitrate (NO₃⁻) supplementation.

Methods: Thirty endurance-trained male participants were allocated to one of three groups: hypoxia (13% F_iO₂) + NO₃⁻; hypoxia + placebo; and normoxia (20.9% F_iO₂) + placebo. All performed 12 cycling sessions (eight sessions of 2*6 × 1 min at severe intensity with 1 min recovery and four sessions of 4*6*10 s all-out with 20 s recovery) during a 4-week period (three sessions/week) with supplementation administered 3–2.5 h before each session. An incremental exhaustion test, a severe intensity exercise bout to exhaustion (T_lim) and a 3 min all-out test (3AOT) in hypoxia (F_iO₂ = 13%) with pulmonary oxygen uptake ( $\dot{V}$ O₂), $\dot{V}$ O₂ kinetics, and changes in vastus lateralis local O₂ saturation (SmO₂) measured were completed by each participant before and after training.

Results: In all tests, performance improved to the same extent in hypoxia and normoxia, except for SmO₂ after T_lim (p = 0.04, d = 0.82) and 3AOT (p = 0.03, d = 1.43) which were lower in the two hypoxic groups compared with the normoxic one. Dietary NO₃⁻ supplementation did not bring any additional benefits.

Conclusion: Performance at simulated altitude was not improved to a larger extent when high-intensity interval training was undertaken in normobaric hypoxic conditions, when compared with normoxic training. Additionally, dietary NO₃⁻ supplementation was ineffective in further enhancing endurance performance at simulated altitude.

9,740 views

4 citations

Open for submission