Author(s): BIZJAK, D., JOHN, L., MUNK, M., REITER, M., LÜDERS, N., KIRSTEN, J., HENZE, A.S., SCHULZ, S.V.W., Institution: UNIVERSITY HOSPITAL ULM, Country: GERMANY, Abstract-ID: 875

INTRODUCTION:
Endurance training camps, typically lasting several weeks and often conducted at high altitude, are an established component of elite endurance training. Recently, one- or two-week training camps for recreational endurance athletes have gained popularity, promising performance improvements, enhanced recovery, and lifestyle benefits. However, scientific evidence supporting these claims is scarce. This study therefore investigated the effects of a one-week endurance training camp on body composition, athletic performance , and blood- and saliva-based markers assessing metabolic and mitochondrial function in recreational endurance athletes.
METHODS:
Female and male endurance athletes aged ≥18 years participating in a one-week training camp focused on running and cycling were examined. Assessments included anthropometry (bioelectrical impedance analysis), running performance (lactate diagnostics), sleep quality (questionnaires), nutritional intake and energy balance (diaries), blood profiling, and markers of mitochondrial biogenesis (Vascular endothelial growth factor [VEGF], Growth differentiation factor 15 [GDF-15], mitochondrial DNA, and PGC1-alpha expression). Plasma markers included creatine kinase, lactate dehydrogenase (LDH), klotho, interferon-gamma, and kynurenine, while saliva markers comprised cortisol, C-reactive protein, and uric acid. Measurements were performed the week before the camp (pre), during the training week (camp), and the week after the camp (post).
RESULTS:
Thirty-five participants (18 male/17 female; 46.4±14.0 years) were included. Body mass and body fat decreased from pre-camp to post-camp, accompanied by adaptations in phase angle and the lactate metabolism. At post-camp, LDH, klotho, and vitamin D concentrations increased, while interferon-gamma, kynurenine, cortisol, creatinine, and ferritin decreased compared with pre-camp. VEGF decreased following the camp, whereas plasma mitochondrial and nuclear DNA relative abundance and PGC1-alpha expression increased post-camp.
CONCLUSION:
Physiological adaptations and metabolic alterations with concomitant reduction of mental stress markers may be achieved during a one-week long endurance training camp in a holiday-like setting. However, the observed muscular and cellular damage indicates that training regimes should be refined and professionally supervised to avoid pathological overreaching. Pre-participation health assessments and individualized training plans are recommended to reduce injury risk and further increase mental well-being.