This study was undertaken to examine the effect
of a heavy weight training exercise on sprinting performance and on the effect
of repeated exposure to a complex training protocol. Eleven male rugby union players
(age 20.9 ± 3.1 years) participated in the study, which involved five separate
testing sessions. Back squat 3RM was established in session one. Sessions two to five were identical and
involved the subjects completing a 30 m sprint before and after a 3RM back
squat protocol. Four minutes rest was given between the back squatting and the
post-test 30 m sprint. All sprint trials were measured with a laser measurement
device (LAVEG, Jenoptik). Sprint time and instantaneous, average and maximum velocity were the
dependent variables. The criterion for
significance was set at an alpha level of p ≥ 0.05. No significant improvement
was evident for any of the testing sessions (p ≥ 0.05). In session one there
was a significant increase in 30 m time and a significant reduction in average
30 m velocity and maximum velocity (p < 0.05). The expected benefits in
sprinting may not have been realised due to intra- and inter-subject variations
in sprint technique. The session × phase interaction revealed a significant
improvement in the pre- to post-test changes in instantaneous velocity at 20 m (p
= 0.035) and 30 m (p = 0.036) from session one to session four. This indicates
that the rugby players may be able to learn to apply the potentiation effects
of complex training. From a practical perspective, players may need repeated
exposure to this training modality to gain benefit from it and this should be
reflected in programme planning.