The effects of age and training prescription on the acute responses to training in young Italian Rugby Union players

EFFECTS OF AGE AND TRAINING PRESCRIPTION ON THE ACUTE RESPONSES TO TRAINING IN YOUNG ITALIAN RUGBY UNION PLAYERS S. Spinabelli, F. Nigro, S. Marcora Department for Life Quality Studies; Bologna Alma Studiorum University, Department of Biomedical and Neuromotor Sciences; Bologna Alma Studiorum University Purpose: The purpose of this study is to understand the moderating effect of age on the internal training load and acute responses to two different training prescriptions in young rugby union players Methods: We measured the acute responses to High Intensity Training (HI) and Low Intensity Training (LI) in three groups (U15 n = 8, U17 n = 10 and U19 n = 9) of young Italian rugby players. HI training consisted of breakdown and wrestling activity alternating with aerobic power exercise, with small-sided games at the end, while training LI consisted entirely of small-sided games with non-contact for technical and tactical objectives, both ninety minutes total. The two training workouts were part of the normal weekly training routine. The following validated questionnaires were used to monitor the acute training effects: Rating of Perceived Effort scale (RPE), Total Quality Recovery scale (TQR), Main and Grove (MG) questionnaire that monitors training distress in athletes, Fatigue (FAT) and Fatigability (FAB) scales. Repeated measure analysis of variance (2x3 ANOVA) was used to analyze RPE, FAT and FAB with respect to Age and Training type, while a 2x2x3 mixed ANOVA was used for MG and TQR questionnaires to further analyze the interactions of Time, Age and Training type. All post hoc analyses were performed following the Bonferroni correction procedure, setting the significance at a p value <0.05. Results: Only a significant Training type by Age by Time interaction for the Sleep Disturbances subscales was found. Perceived effort was significant for age by training type interaction. Follow up test revealed that U17 group was statistically different for both conditions, while in the U19 group was just near to the threshold. The main effect of training type was statistically significant for FAB scale. Only in post training condition we found significant main effects of Training type and Age for the Physical Symptoms subscale. Conclusions: The RPE and FAB scales are most sensitive to acute effects of training load for group U17 and U19, while under the age of 15 do not seem to provide valid ratings of sRPE. With the possible exception of Physical Symptoms subscale of the Main&Grove questionnaire, TQR and the other Main&Grove subscales are not sensitive to acute differences in training load. The Training Monitoring strategy used in the present research represents a valid approach to control training sessions acute effects in young rugby union teams. References: Jeffries A. C.; Marcora S. M.; Coutts A. J.; Wallace L.; McCall A.; Impellizzeri F. M. Development of a Revised Conceptual Framework of Physical Training for Use in Research and Practice; Sport Medicine 2021. Foster C., Florhaug J. A., Franklin J., Gottschal L., Hrovatin L. A., Parker S., Doleshal P., Dodge C.; A New Approach to Monitoring Exercise Training; Journal of Strength and Conditioning Research, 2001, 15, 109–115.