Author(s): KRALIK, M., KRAL, R., HADZA, R., Institution: AKADEMIA TELOCVIKU, Country: SLOVAKIA, Abstract-ID: 1488

INTRODUCTION:
The minimum velocity threshold (MVT) is one of the crucial metrics using velocity-based devices for prediction one repetition maximum (e1RM), from non-maximal loads. MVT is the mean concentric velocity (MCV) produced during the last successful repetition of a set and another way to acquire velocity for a 1RM (1). These velocities are afterwards also used for objective real-time monitoring, prescribing and adjustment of the training load and training intensity. We know, that for different exercises have different MVTs, but authors also have different recommendations for free-weight bench press 0.18 m/s-1 (2) and 0.17 m.s-1(4), which is most widely used. Therefore, the aim of this study was to examine differences of MVT in free-weight bench press (BP) exercise in national level youth kayak athletes and the accuracy of the estimation. This exercise was chosen because its use in strength and conditioning training of kayak athletes and can affect the sport performance in sprint kayak (5).
METHODS:
14 resistance trained athletes (5 females, 9 males; 14-20 years of age) with minimum of 2 years of strength training experience were recruited for this study. All subjects performed a one-repetition maximum test (1RM) on BP with measuring their MCVs using Tendo unit. Subjects trained for last year 3 times a week and were familiar with BP. The individual MVTs were compared with general recommended MVTs and the individual 1RMs were compared with e1RM.
RESULTS:
MVTs of 1RMs on free-weight bench press varied widely in athletes from 0.12 m.s-1 to 0.32 m.s-1. The average of the MVTs in the group was 0.21 m.s-1, with SD=0.065 m.s-1. The mean value of 1RM was 54.6kg (SD=24.4) vs. e1RM 57.6 kg (SD=25.9). Even though the two-way mixed effect model with single measures ICC=0.98. In one example subject was 9.98% difference in 1RM vs e1RM (90kg vs 98.7kg).
CONCLUSION:
We found high differences in BP MVTs in our athletes and differences of the average in the group compared to recommended (0.21 vs 0.17). So, we suggest that more precise would be to establish MVT for each athlete individually and use it later in testing and training. With these findings we would recommend restraining international level athletes from using standard MTVs. We even found that these standards for BP were mostly performed as smith machine bench press, which is much less common type of pressing oriented exercise, and less adequate due to lower attained velocities compare to free-weight BP. The standard MVT 0.17 m.s-1 (used in various velocity-based training devices) caused not only overestimations but also underestimations in 1RMs. In later we would recommend to app developers to add possibility of entering individual MVT for each exercise to precisely evaluate e1RM and use this kind of technology for training purposes.

REFERENCES

1. Signore, Human Kinetics 2021
2. Loturco et al, JSCR 2017
4. Greig et al, Sports Medicine 2023
6. Kristiansen et al, JSCR 2023

FUNDING: This study was supported by the Grant No. VEGA 1/0415/23