Monitoring Physiological Adaptations in Male Volleyball Athletes During a Microcycle of Preparation

Abstract

2079 In Brazil, volleyball is a very popular sport. Recently, the national teams have achieved great performances in the world championships for adults, under-21 and under-19 categories. These athletes regularly are submitted to heavy workloads during the training sessions which induce to many physiological adaptations. PURPOSE: To monitor the training adaptations on the sympathetic nervous system (SNS) in male athletes of the under-19 years old Brazilian national team during the preparation for the 2001 world championship by the urinary excretion of the vanil mandelic acid (VMA). Considering that training adaptations after a certain period occur due to the workloads applied, this study also had as an objective to monitor the intensity (HR/bpm) and volume (number of repetitions of each skill) of each session evaluated. The athletes were classified as Setters, Middle blockers and Outside hitters. METHODS: The sample was composed of 17 athletes (age: 18,0 ± 0,5 years old; height: 197,1 ± 3,9 cm; body weight: 87,8 ± 6,3 kg). The data were collected in four different micro cycles of the 22 weeks long macro cycle. The overnight urine samples were collected in the morning after a normal night of rest for the determination of the VMA. RESULTS: The mean heart rate was 132 ± 18 bpm. By quantifying the training volume it was possible to verify that the workloads were applied according to the specificity of each athletes' function. There were no significant statistical differences on the values of VMA excretion in mg/l (F 0,10; p 0,9036) and total VMA excretion in mg (F 0,01; p 0,9874) both at p<0,05, considering the three functions. The VMA excretion decreased significantly for both VMA excretion in mg/l (F 9,14; p 0,0001) and total VMA excretion in mg (F 11,67; p 0,0001) during the four moments evaluated. CONCLUSION: These results could be associated with an important training adaptation on SNS to the workloads, since the short periods of intense effort alternated with short periods of recovery, that characterize the volleyball, seemed to represent a strong stimuli to SNS to promote the verified adaptations on the values of VMA excretion. Supported by CENESP/UEL and Ministry of Sports-Bazil