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  • Author: Karsten Koehler x
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Case Study: Improving Energy Status in a Wheelchair Athlete With Suppressed Resting Energy Expenditure

Joelle Leonie Flueck and Karsten Koehler

Purpose: Wheelchair athletes experience a reduction in fat-free mass due to the underlying condition and/or muscle disuse. This leads to a lower resting energy expenditure (REE), as well as a lower energy expenditure during exercise or daily activities. Traditional markers of low energy availability (LEA), including amenorrhea and low bone mineral density, are often inconclusive in wheelchair athletes. This case study provides data from a professional female wheelchair badminton player with multiple sclerosis who presented with a reduced measured-to-predicted REE ratio (REEratio), a common indicator of LEA in able-bodied athletes. Furthermore, a nutrition and exercise intervention was conducted to restore REE. Methods: REE and body composition were measured using indirect calorimetry and dual-energy X-ray absorptiometry, respectively. The predicted REE of the REEratio was calculated using 2 separate approaches. An REEratio <0.9 was considered an indicator for LEA. A nutrition and exercise intervention was implemented to normalize REE and induce weight loss through increased meal frequency, a 200- to 400-kcal/d increase in energy intake, and added endurance exercise. Results: The athlete (33 y, 78 kg, 154 cm) initiallly showed an REEratio of 0.65 to 0.70, which increased to 1.00 to 1.09 after 1 year. The athlete lost 11.8 kg, almost exclusively (11 kg) in the form of fat mass. The athlete reported reduced fatigue and higher perceived fitness. Conclusion: The nutrition and exercise intervention successfully restored energy status, induced sustainable weight loss, and reduced fatigue in a wheelchair athlete with multiple sclerosis with presumed LEA. Methods to assess LEA in this population require further validation.

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Association Between Energy Balance and Metabolic Hormone Suppression During Ultraendurance Exercise

Bjoern Geesmann, Jenna C. Gibbs, Joachim Mester, and Karsten Koehler

Ultraendurance athletes often accumulate an energy deficit when engaging in ultraendurance exercise, and on completion of the exercise, they exhibit endocrine changes that are reminiscent of starvation. However, it remains unclear whether these endocrine changes are a result of the exercise per se or secondary to the energy deficit and, more important, whether these changes can be attenuated by increased dietary intake. The goal of the study was to assess the relationship between changes in key metabolic hormones after ultraendurance exercise and measures of energy balance. Metabolic hormones, as well as energy intake and expenditure, were assessed in 14 well-trained male cyclists who completed a 1230-km ultraendurance cycling event. After completion of the event, serum testosterone (–67% ± 18%), insulin-like growth factor-1 (IGF-1) (–45% ± 8%), and leptin (–79% ± 9%) were significantly suppressed (P < .001) and remained suppressed after a 12-h recovery period (P < .001). Changes in IGF-1 were positively correlated with energy balance over the course of the event (r = .65, P = .037), which ranged from an 11,859-kcal deficit to a 3593-kcal surplus. The marked suppression of testosterone, IGF-1, and leptin after ultraendurance exercise is comparable to changes occurring during acute starvation. The suppression of IGF-1, but not that of other metabolic hormones, was strongly associated with the magnitude of the energy deficit, indicating that athletes who attained a greater energy deficit exhibited a more pronounced drop in IGF-1. Future studies are needed to determine whether increased dietary intake can attenuate the endocrine response to ultraendurance exercise.

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Table Tennis: Cardiorespiratory and Metabolic Analysis of Match and Exercise in Elite Junior National Players

Billy Sperlich, Karsten Koehler, Hans-Christer Holmberg, Christoph Zinner, and Joachim Mester

Purpose:

The aim of the study was to determine the cardiorespiratory and metabolic characteristics during intense and moderate table tennis (TT) training, as well as during actual match play conditions.

Methods:

Blood lactate concentration (Lac), heart rate (HR, beats per minute [bpm]), oxygen uptake (VO2), and energy expenditure (EE) in 7 male participants of the German junior national team (age: 14 ± 1 y, weight: 60.5 ± 5.6 kg height; 165 ± 8 cm) were examined during six training sessions (TS) and during an international match. The VO2 was measured continuously with portable gas analyzers. Lac was assessed every 1 to 3 min during short breaks.

Results:

Mean (peak) values for Lac, HR, VO2, and EE during the TS were 1.2 ± 0.7 (4.5) mmol·L–1, 135 ± 18 (184) bpm, 23.5 ± 7.3 (43.0) mL·kg–1· min–1, and 6.8 ± 2.0 (11.2) METs, respectively. During match play, mean (peak) values were 1.1 ± 0.2 (1.6) mmol·L–1, 126 ± 22 (189) bpm, 25.6 ± 10.1 (45.9) mL·kg–1·min–1, and 4.8 ± 1.4 (9.6) METs, respectively.

Conclusions:

For the frst time, cardiorespiratory and metabolic data in elite junior table tennis have been documented demonstrating low cardiorespiratory and metabolic demands during TT training and match play in internationally competing juniors.