The effect of training on peripheral neuromuscular fatigue induced by repeated change of direction in basketball

Introduction Change of direction (COD) is considered an important physical determinant of basketball performance (McInnes, 1995). Understanding how COD can influence physical abilities may provide insights into player performance. Optimal training load (TL) prescription, during the preparation phase of the season, is required to optimize player performance. Relationships between TL and changes in player fitness have been investigated in team sports such as soccer and rugby (Jaspers, 2016) but never in basketball. This study aimed to quantify changes in peripheral neuromuscular fatigue induced by repeated CODs after the preparation period and to determine their relationships with the TL (sRPE) sustained by professional (PRO) and semi-professional (SPRO) basketball players. Methods Pre (T1) and Post (T2) the preparation period, peripheral neuromuscular function of the knee extensors (peak torque, PT) was measured using electrical stimulation during a repeated 180° COD test, consisting of 4 levels with increasing intensities (PT1, PT2, PT3 and PT4), in 12 PRO and 16 SPRO basketball players. Furthermore, PT_MAX (the highest value of PT) and PT_DEC (PT decrement from PT_MAX to PT4) were also calculated. Results At T2, from possibly to likely lower PT1 (PRO: 69.8±10.9 vs 65.0±10.1 Nm; SPRO: 61.8±14.8 vs 58.7±13.2 Nm) and PT2 (PRO: 76.2±11.8 vs 72.2±10.8 Nm; SPRO: 68.3±14.9 vs 64.4±13.9 Nm) were observed in both groups, while a very likely greater PT4 was found in PRO (56.0±19.6 vs 65.8±15.3 Nm) and SPRO (50.6±16.5 vs 58.7±13.3 Nm). No clear variation was observed in PT_MAX in PRO (76.8±12.0 vs 73.8±11.5 Nm), while a possible reduction was found in SPRO (69.1±14.6 vs 65.6±13.9 Nm). Reductions in PT_DEC were almost certain in PRO (27.8±21.3 vs 11.4±13.7%) and very likely in SPRO (26.1±21.9 vs 10.2±8.2%). Moderate relationships were found between TL and changes in PT1 (r=-0.45±0.26), PT2 (r=-0.44±0.26), PT3 (r=-0.40±0.27) and PT_MAX (r=-0.38±0.28). Discussion The current findings suggest that the ability to sustain repeated CODs efforts may be improved after the preparation period, as peripheral neuromuscular fatigue induced by a COD test was reduced in both groups. Small reductions in PT were observed when CODs were performed at low and medium-low intensities. The observed relationships suggest that high TL may negatively affect peripheral neuromuscular function during the preparation period. References Jaspers A, Brink M, Probst S, Frencken W, Helsen W. (2016). Sports Med, [Epub ahead of print]. McInnes S, Carlson J, Jones C, McKenna M. (1995). J Sports Sci, 13(5),387-97.