Purpose:
The aim of the study was to evaluate the effects of a decrease in hold size, change in the safety rope protocol, and rest period shortening on heart rate (HR), heart rate variability (HRV), pre-climb anxiety, and perceived workload in sport rock climbers under laboratory settings.

Methods:
A total of 12 intermediate sport rock climbers were recruited. The participants completed 2 routes of different climbing difficulty. They repeated the difficult route with a short 5-minute rest period 3 times and repeated the same route with a change to lead climb. HR, HRV, anxiety level (Competitive State Anxiety Inventory-2 Revised), and climbing workload (NASA_climbing questionnaire) were measured.

Results and conclusions:
It was lead climb that elicited the most noticeable psychophysical response in the intermediate climbers. Prior to the climb, the performers exhibited marked sympathetic activation and higher cognitive anxiety. Climbing HR_peak was correlated with physical workload, psychological demand, and increasing fatigue; hence, it can be considered a variable that reflects the accumulative psychophysiological stress. NASA_climbing score effectively reflected differences in physical load (physical demand – strength and endurance) and psychological load (higher mental demand, temporal demand, and satisfaction level) during climbing.