Training and 24-hr Urinary Catecholamine Excretion

We examined the effects of 28 weeks of training on 24-hr urinary catecholamine excretion and mood (evaluated using the Recovery-Stress Questionnaire for Athletes RESTQ-Sport) among seven national young female tennis players. Data were collected after a 1-month rest (September, T-1), 3 months after T-1 (T-2) and 7 months after T-1 (T-3)- Standardized Stress and Standardized Recovery scores and RESTQ-Index were computed. The training load increased by 161% between T-1 and T-2 and by 55% between T-2 and T-3. The performance (wins/total number of matches) decreased throughout the Study. Urinary catecholamine excretion presented an U-shaped curve with a significant increase in 24-hr urinary catecholamine excretions, and epinephrine/norepinephrine ratio from T-1 to T-2 (T-1 vs. T-2: epinephrine: + 100%, p < 0.05; norepinephrine: + 30%, p < 0.05. Then, at T-3, urinary catecholamine excretions and the epinephrine/norepinephrine ratio decreased significantly to values lower than the values observed at T-1. A decrease in RESTQ-Index throughout the Study was mainly based on a large increase in the Standardized Stress score. Changes in specific stress and recovery scales of the RESTQ-Sport for athletes and changes in catecholamine values indicated a state of heavy training stress and incomplete recovery at the end of the study.