Author(s): WIEDENMANN, T., RAPPELT, L., HELD, S., WAGNER, L., DONATH, L., Institution: GERMAN SPORT UNIVERSITY COLOGNE, Country: GERMANY, Abstract-ID: 2040

INTRODUCTION:
Velocity based (strength) training (VBT) has been recognized as an effective method for controlling training volume and quality [1]. Studies have demonstrated that a training with velocity loss thresholds (VLT) results in increased maximal strength as well as improved sprinting and jumping performance compared to traditional resistance training [2]. Unfortunately, available velocity and acceleration sensors are expensive and can impose practicability issues. Hence, the objectives of this study were to evaluate (I) the accuracy of velocity perception for strength trained participants during the barbell bench press and (II) whether a single habituation session with VLT feedback can beneficially affect the perceived 20% VLT’s agreement with the true values.
METHODS:
Eighteen strength trained participants (n (female, male) = 10, 8; age: 26 ± 5 years; 177 ± 10 cm; 79,3 ± 27,6 kg; ≥ 2 years of bench press experience), without prior VBT experience, completed 4 individual sessions, separated by 48 h. Session 1 served as an instruction session and one repetition maximum (1RM) assessment. In session 2 and 4, the participants completed 3 sets at 80 % 1RM. For each set, the participants were instructed to give a verbal cue when they estimated a relative loss of velocity ≥ 20% (20%VLT) and continued their set until failure (≤ 1 repetitions (reps) in reserve). In session 3 the participants were familiarized with a VLT training and completed 3 sets of bench press at 70% 1RM until the 20%VLT was reached. Bench press velocity and reps were monitored, analysed for agreement and presented as bias with limits of agreement (LoA).
RESULTS:
The participants performed an average of 9.9 ± 2.1 reps to failure across all sets in session 2. The mean number of reps completed at the 20%VLT was 4.5 ± 1.3 and the mean velocity at 20%VLT was 0.33 ± 0.07 m/s across sets. The participants slightly underestimated the repetitions until 20%VLT by -0.3 reps (LoA [-1.7, 1.2]) which resulted in a slight overestimation of velocity at 20%VLT by 0.02 m/s (LoA [-0.05, 0.08]). There was no change after the familiarization in session 3 for the reps (bias = -0.24, LoA [-1.60, 1.12]; Cohen’s d = 0.015, p = 0.93), or velocity (bias = 0.01 m/s, LoA [-0.05, 0.07]; Cohen’s d = -0.107, p = 0.48).
CONCLUSION:
The analysis of agreement between the perceived and true repetitions and velocity at the 20%VLT reveals a small bias for the bench press with high load. A single habituation session does not meaningfully affect this bias. Our findings indicate that a VLT training can alternatively be applied without velocity measurement, if the athletes are moderately strength trained. Future studies should expand on the current findings with respect to different exercises and load ranges.
1. Weakley J, Mann B, Banyard H, McLaren S, Scott T, Garcia-Ramos A. Strength & Conditioning Journal. 2021;43:31–49.
2. Held S, Speer K, Rappelt L, Wicker P, Donath L. Front Physiol. 2022;13:926972.