Physiological and Molecular Adaptations to Different Training Modalities in National-level Kayak Athletes

This interventional study evaluated physiological, molecular, and performance adaptations to different high-intensity training modalities in national-level kayak athletes. Thirty-two athletes were allocated to four parallel groups: high-intensity interval training (HIIT), sprint interval training (SIT), combined training (COMB), or a control condition (CON). The study protocol included a six-week detraining period before baseline (PRE) assessments, followed by a six-week training intervention and a subsequent six-week detraining period. Physiological assessments and blood sampling were performed at PRE and immediately after the training intervention (POST) to evaluate training-related changes. Sprint kayak performance over 500 m was assessed at PRE and POST, with additional assessments conducted 15 and 30 days after completion of the subsequent six-week detraining period. The study aimed to examine the effects of different training modalities on physiological responses, circulating molecular markers, and 500-m kayak performance, as well as changes in performance following detraining.

Inclusion Criteria: * National-level flatwater kayak athlete. * At least 4 years of systematic kayak training experience. * Active participation in kayak training and competition. * Able to complete the prescribed training interventions and physiological and performance testing procedures. Exclusion Criteria: * Injury or illness that prevented participation in the training intervention or testing procedures. * Inability to complete the prescribed intervention or required study assessments.