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Effects of a Deca Iron Triathlon on body composition: a case study
B Knechtle1, P Knechtle, R Schück
1St Gallen, Gesundheitszentrum, St Gallen, Switzerland. beat.knechtle@hispeed.ch
International Journal of Sports Medicine
|September 21, 2007
Summary
Ultra-endurance athletes experience significant energy deficits during multi-day triathlons. This study found that a Deca Iron Triathlon led to a substantial loss of both fat and muscle mass, alongside increased body water.
Area of Science:
- Sports Science
- Human Physiology
- Endurance Sports Medicine
Background:
- Ultra-endurance events like the Deca Iron Triathlon demand extreme physiological adaptation.
- Understanding energy balance and body composition changes is crucial for optimizing performance and health in these athletes.
Observation:
- A single male ultra-endurance triathlete was monitored during a 10-day Deca Iron Triathlon.
- Measurements included body mass, skinfolds, perimeters, energy intake, and expenditure (using heart rate monitoring).
- Bio-impedance analysis assessed fluid metabolism throughout the event.
Findings:
- The athlete completed the race in 128:22:42, finishing 3rd.
- Significant reductions were observed: body mass (-1 kg), skeletal muscle mass (-0.9 kg), and fat mass (-0.8 kg).
- Total body water increased by 2.8 liters, with a total energy expenditure of 89,112 kcal and an energy deficit of 11,480 kcal.
Implications:
- The energy deficit was likely met by metabolizing adipose and skeletal muscle tissue.
- Muscle mass degradation may contribute to hypoproteinemic edema in ultra-endurance athletes.
- Further research is needed to fully understand the long-term physiological consequences.
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