This is the abstract of the thesis I did during my Master of Science in Sport Science in Bologna, Italy. It has been presented at the BASES Student Conference 2019, and the abstract was published on the Graduate Journal of Sport, Exercise & Physical Education Research (2019) Vol. 11, Suppl.1: S73
Authors: Samuele Di Nicola, Rocco Di Michele
The bench press (BP) is a popular weight training exercise and one of the lifts used in powerlifting. However, there is limited research on the biomechanical analysis of two common BP techniques, flat and arched back, in elite powerlifters. Garcia-Ramos et al. (2018, Sports Biomechanics, 11,1-13) analysed the differences in one-repetition maximum (1RM) and load-velocity profile between flat and arched technique in competitive powerlifters, showing no 1RM difference between them. However, no previous studies have analysed the role of lower limbs during the BP. Therefore, the aim of this study was twofold: a) using Inertial Measurement Unit (IMU) and force plates to analyse flat and arched techniques in elite powerlifting athletes (PL) b) compare results from flat technique with a control group (CG). Following institutional ethics approval, seven participants (age: 28.13 ± 6.53 years; height: 176.5 ± 8.04 cm; body mass: 82.56 ± 8.89 kg) (4 in PL group and 3 in CG) performed single lifts at different loads (50/ 60/ 70/ 80/ 90% of 1RM). CG performed three repetitions for every load using only the flat technique, whereas PL performed two repetitions for every load, using both techniques. Data were analysed using independent and paired sampled t-tests, with all data presented as means ± standard deviation. CG participants had a flat 1RM of 123.75 ± 9.46 kg and a 1RM/Body Mass (BM) ratio of 1.46 ± 0.07. Absolute and relative strength of PL participants were flat 1RM – 128.75 ± 24.96 kg; arch 1RM – 143.75 ± 21.75 kg; flat 1RM/BM – 1.60 ± 0.2; arch 1RM/BM – 1.79 ± 0.18, respectively. Results in PL group showed a significantly higher maximum force with arched technique compared to flat (+10.1%; P < 0.01). The arched technique also resulted in lower maximum velocity (-13.99%; P < 0.01) and power (-3.66%; P = 0.61). Between-group analysis revealed higher maximum force in CG group (+3.12%; P = 0.10). Force plates results showed a specific vertical ground reaction forces (vGRF) pattern based on the lifting phase in PL group, which indicated a greater control and balance compared to CG. In conclusion, PL athletes appear to produce more force but less power and speed using the arched technique. The findings from the IMU show that PL training methods can lead to higher strength gains and improved balance, although further studies are required to explain the differences between the two techniques.