Introduction

Successful training is a key for athletes to make progress in their development. Training must not just involve overload, but also must prevent the combination of excessive overload plus inadequate recovery. Athletes can experience short-term performance decrement without severe psychological or lasting other negative symptoms. Too much hard exercise or too little sleep can cause overtraining, a condition in which the subject can prevent to be away from the sport for several weeks or months. Previous studies have detected that it is important to avoid overtraining. A reliable method is currently not available to detect the warning signs in time to prevent it.

AIM:  When physical performance deteriorates with overtraining is the purpose of the current study to determine whether impaired explosive strength performance (CMJ) is related to the change in HRV and static strength (grip strength) between the best and worst test day during one season.

Purpose and Methods: Variation in CMJ was investigated in eight elite floorball players (four women and four men). Heart rate variability (HRV) was measured using a heart rate monitor. The subjects were in supine position for ten minutes and changed into a standing position for eight minutes when HRV was recorded. After the mentees had performed HRV recording, three CMJ jumps and grip strength test was made where the best result was noted. This jump and grip strength was done to check upper and lower body strength.

Results: Significant differences were detected in CMJ, HRV, but not in grip strength. In HRV occurred the significance of all the variables, but the most obvious differences were detected in average heart lying/standing and resting heart rate.

Conclusions: Significant differences were detected in CMJ, HRV but not in the grip strength. Impaired explosive strength (CMJ) is related to changes in HRV, but not static strength.

Keywords: Heart rate variability, Overreaching, Overtraining.