Resistance training for sprinters : the role of maximum strength, reactive strength and exercise selection

Each distinct phase of a 100 m sprint is dependent on key race variables e.g. acceleration ability, maximum velocity and speed endurance. Consequently, sprinters frequently supplement their sprint training with resistance training to develop qualities such as maximum strength and reactive strength. The literature assessing the association between these strength qualities and sprint performance has found contrasting results. Additionally, the literature on the prescription of resistance exercises to sprinters is sparse and consequently, evidence based prescription of resistance training is limited. Thus, the aims of this programme of research were to explore the relationship between race variables and 100 m time, explore the role of maximum strength and reactive strength in sprinting and to investigate the prescription and suitability of resistance training exercises for sprinters. Chapter 3 investigated world class male 100 m sprint performance data and found that the acceleration-time constant was an excellent indicator of relative acceleration ability and therefore merits monitoring. Furthermore, maximum velocity was highly related to each 20 m section of the sprint (r = -0.57 to -0.98) and overall 100 m time (r = -0.97) highlighting the crucial importance of maximum velocity to a 100 m sprinter. Chapter 4 investigated the relationship between maximum strength, reactive strength and maximum velocity, 10 m split times and sprint mechanical properties assessed during a 40 m sprint. Peak force and relative force, measured in an isometric mid-thigh pull, and reactive strength index, measured in drop jumps and hopping, had no statistically significant relationship with any of sprint performance measures. However, a high correlation (r = 0.61) was found between peak force and peak horizontal power in men only. The lack of a significant relationship between drop jump reactive strength and any of the sprint performance measures indicated that the use of the reactive strength index as a measure of an athlete’s reactive strength warranted further investigation. Consequently, Chapter 5 assessed how differing performance strategies affect measures of reactive strength in drop jumps. Limiting group variance in contact time was recommended to improve the validity of reactive strength measurements. In Chapter 6 a survey of sprint coaches’ prescription of resistance training exercises was conducted with the hurdle jump found to be the most widely prescribed exercise (93% of coaches). Based on the findings of Chapter 6, a biomechanical comparison between the kinematics of maximum velocity sprinting and hurdle jumping was conducted in Chapter 7. Based on Chapter 7’s findings, the hurdle jump is recommended as a suitable exercise for sprinters due to the greater demand placed on the athlete to reverse the velocity of their centre of mass, similar peak knee extension angular velocities and greater ankle dorsiflexion angular velocities. Common themes emerging from the thesis are also discussed including the implications for using ratio-based measures, using ground contact time as a monitoring tool and recommendations for individualised assessment and training.