Normalization of training loads in biathletes using indicators of heart rate cost and energy expenditure

Aim. The aim of this study was to investigate the use of heart rate (HR) cost and the energy expenditure of exercise to optimize training loads for highly skilled biathletes. Materials and methods. The study involved highly skilled biathletes (MS, ICMS, MMS) who performed an incremental exercise test with measurement of lactate concentration, walking speed, maximum HR, and average HR. Blood lactate concentration was determined electrochemically (Super GL easy, Dr. Muller, Germany) from capillary blood samples taken at the end of each load stage. Gas exchange and HR were recorded continuously using a MetaMax 3B mobile spiroergometry system. The relationship between HR, lactate, and walking speed was analyzed. For lactate analysis, portable Lactate Pro 2 test meters were used. Heart rate was recorded using Polar Vantage V2 multisport watches and the Polar Flow app. Results. As the load increased to the anaerobic threshold, a linear relationship was recorded between heart rate / VO2max and movement speed. At intensities exceeding the anaerobic threshold, the heart rate and blood lactate levels changed nonlinearly. Under these conditions, the HR cost objectively reflected the dynamics of the athletes’ adaptation processes and their efficiency in performing the load. Conclusion. The use of HR cost, in combination with lactate concentration, enables effective monitoring and management of the training process for biathletes using cyclic training methods, without the need for complex gas analysis systems.