Author(s): MEI, T., ZHANG, X., LI, J., LI, L., Institution: BEIJING SPORT UNIVERSITY, Country: CHINA, Abstract-ID: 367

INTRODUCTION:
Autoregulatory Training (ART) can adjust training loads based on athletes training status. It includes Velocity Based Training (VBT) and Repetition in Reserve (RIR) based on subjective perception of fatigue (Rating of Perceived Exertion, RPE). However, there is limited research on the mechanical characteristics of these two methods. This study aimed to compare and analyze the biomechanical characteristics of sprinters in a single free squat training session using traditional Percentage-Based Training (PBT), RIR, and VBT, aiming to provide an individualized training load regulation protocol for sprinters.
METHODS:
18 male sprinters were recruited, and a randomized crossover experimental design was used for 3 randomized crossover squat training sessions (PBT, RIR, and VBT). Under an 80% 1RM load, the PBT group completed 5 sets of 5 repetitions each, the RIR group completed 5 sets of 5 repetitions each, with the load for the next set adjusted based on subjective feedback from the subjects, and the VBT group completed 5 sets of training, stopping each set when the speed decreased to 80% of the mean speed. Linear position sensors (Tendo) were used to collect mechanical indices (including Mean velocity (MV), Mean force (MF), Mean power (MP), Mean work (MW), Peak velocity (PV), Peak force (PF), Peak power (PP), Total work (TW), Mean load (ML), Mean repetitions (Reps), Total time under load (TUT), and Total time under load (sTUT)) and subjective perception (RPE) during the squat training. Performing data analysis using one-way analysis of variance (ANOVA).
RESULTS:
(1) The VBT group had the fastest Mean velocity (MV) (PBT, VBT, and RIR MV: 0.53±0.05m/s, 0.58±0.05m/s, and 0.55±0.04m/s, respectively, p<0.05). The Peak velocity (PV) of the VBT and RIR groups was significantly faster than that of the PBT group (PBT, VBT, and RIR PV: 0.91±0.06m/s, 1.00±0.06m/s, and 0.97±0.06m/s, respectively, p<0.05). The Mean power (MP) of the VBT and RIR groups was significantly higher than that of the PBT group (PBT, VBT, and RIR MP: 729.39±61.23w, 800.72±82.64w, and 797.67±83.03w, respectively, p<0.05). The Repetitions (Reps) of the VBT group were lower than those of the PBT and RIR groups (PBT, VBT, and RIR Reps: 25.00±0.00, 24.06±0.73, and 25.00±0.00, respectively, p<0.01). No significant differences were found in other measurements among the three training groups. (2) There were no significant differences among the three groups in CTUT, but sTUT showed significant differences (PBT, VBT, and RIR sTUT: 61.41±2.74s, 54.68±2.04s, and 59.87±2.19s, respectively, p<0.01). (3) Compared to the PBT group, the RPE was lower in the VBT and RIR groups (PBT, VBT, and RIR RPE: 8.00±0.77, 7.44±0.51, and 7.72±0.67, respectively, p<0.05).
CONCLUSION:
VBT and RIR demonstrated faster speed, greater power output, and lower subjective perception in a single free squat training session compared to traditional PBT. Additionally, their effects on time indices were different from PBT.