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Malte Krüger, Markus de Mareés, Karl-Heinrich Dittmar, Billy Sperlich and Joachim Mester

Purpose:

To examine the effects of a whole-body cryotherapy (WBC) protocol (3 min at –110°C) on acute recovery and key variables of endurance performance during high-intensity intermittent exercise in a thermoneutral environment.

Methods:

Eleven endurance athletes were tested twice in a randomized crossover design in which 5 × 5 min of high-intensity running (HIR) were followed by 1 h of passive rest at ~22°C, including either 3 min of whole-body exposure to –110°C (WBC) or a placebo intervention of 3 min walking (PBO). A ramp-test protocol was performed before HIR (R1) and after the 1-h recovery period (R2). Time to exhaustion (t lim) was measured along with alterations in oxygen content of the vastus lateralis (TSI), oxygen consumption (VO2), capillary blood lactate, heart rate (HR), and rating of perceived exertion (RPE) during submaximal and maximal running.

Results:

The difference in t lim between R1 and R2 was lower in WBC than in PBO (P < .05, effect size d = 1.13). During R2, TSI was higher in WBC during submaximal and maximal running (P < .01, d = 0.68−1.01). In addition, VO2, HR, and RPE were lower at submaximal level of R2 after WBC than in PBO (P = .04 to <.01, d = 0.23−0.83).

Conclusion:

WBC improves acute recovery during high-intensity intermittent exercise in thermoneutral conditions. The improvements might be induced by enhanced oxygenation of the working muscles, as well as a reduction in cardiovascular strain and increased work economy at submaximal intensities.

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Karsten Koehler, Frank Huelsemann, Markus de Marees, Bjoern Braunstein, Hans Braun and Wilhelm Schaenzer

During prolonged periods of high energy expenditure (EE), restricted food intake can lead to a loss of body mass. This case study describes the preexpedition support for an unsupported 3-wk crossing of the Atacama Desert in Chile. The goals were to simulate the energy requirements of walking under varying conditions and to predict energy intake and EE to evaluate whether the expected weight loss was in acceptable limits. The expeditionist (male, 35 yr, 197 cm, basal weight 80 ± 0.5 kg) was a well-trained endurance athlete with experience of multiple expeditions. During the simulation, he walked on a treadmill at speeds of 2–7 km/hr under varying conditions of inclination (0%, 7.5%), backpack weight (0 kg, 30 kg), and altitude (sea level, simulated altitude of 3,500 m). Under all conditions, the lowest EE was observed at 5 km/hr. Based on the simulation data, we predicted an average EE of 4,944 kcal/day for the expedition. Because energy intake was restricted to 2,249 kcal/day, we expected the expeditionist to lose considerable weight and consequently advised him to gain 5 kg of body-fat reserves. During the actual desert crossing, he covered a distance of 26 ± 7 km/day at an average speed of 3.8 ± 0.4 km/hr. Daily EE (4,817 ± 794 kcal/day) exceeded energy intake (1,771 ± 685 kcal/day), and the negative energy balance was in agreement with the actual weight loss of 10.5 kg, which was most notable in the lower trunk.