Repeat sprint ability
Generally, a requirement of many team sports and some individual sports is to move at a high intensity for short periods of time in order to complete a game related skill. In football, you may attack a cross to head the ball, in rugby you may sprint to complete a tackle and in tennis you might find yourself turning to chase down and return a lob. The thing that all these sports have in common is that you don’t only complete these movements and skills once during a match, you will find yourself sprinting multiple times for varying periods of time with different periods of rest. So how do we best prepare you to cope with these demands? First we need to understand what aspects of your physiology affect your repeat sprint ability, then we have to figure out the best way to train them.
Team sport activities have the potential to produce high levels of lactacte, particularly during intense periods of play. It is thought that anaerobic pathways are hampered by the build up of acidity in the muscle, and in particular hydrogen ions6, and that this reduces the ability of the muscles to contract reducing the intensity of exercise3. The body attempts to buffer this acidity using naturally occurring bicarbonates. If your ability to buffer lactate is improved, you are able to maintain a higher intensity for a longer period of time, contributing to an improvement in repeat sprint ability. It has been found that much greater improvements in muscle buffer capacity are elicited through high intensity interval training than through continuous exercise at an intensity below lactate threshold1 and that the same research group has found 2 minute intervals at 80% VO2max with one minute rest to be the intensity at which gains seem to be greatest. So it not always necessary to train at maximum intensity during intervals is not always the best for the gains you’re after.
The energy for short term high intensity bursts of activity seen during team sports comes from high energy phosphates within the muscle, namely adenosine triphosphate (ATP) and phosphocreatine (PCr). When you sprint you utilise these phosphates and in order to replenish them, the reactions need oxygen and so re-synthesis of PCr requires aerobic ability. Unpublished work from Bishop et al out of Australia (2004, 2005) and other work5 indicates that the ability to re-synthesise can be improved again through interval training that targets improvements in VO2max and lactate threshold, this occurs at a slightly higher intensity of around 90% VO2max with similar recoveries to those mentioned above. There is currently no research to suggest that repeated or intermittent sprint training improves re-synthesis of PCr however other benefits, including psychological, may be associated with this type of training.
Some readers may be wondering why not just play the sport or develop game specific training sessions to have not only impact on physiological parameters but also developing game based skills. The use of game specific training can work, provided you are able to design sessions to accurately obtain the target intensities for the periods required to get the alterations you’re after but for some sports this can be difficult. In tennis for example, work rest intervals during a match are between 1:3 and 1:54,2, these work periods are too short and rest intervals are too long to stimulate increases in muscle buffer capacity.
So it would seem that interval training has the largest all round impact on repeat sprint ability. The recommendations are that by periodising the number of intervals per session 2-3 times per week for 4-5 weeks improvements in repeat sprint ability can be obtained. Obviously prescription of this sort of program are dependent upon training history, stage of the season, individual goals and positional requirements and should be built into a well designed, individualised strength and conditioning program.
- Edge, J., Bishop, D. & Goodman, C. (2005). The effects of training intensity on muscle buffer capacity in females. European Journal of Applied Physiology, 96(1) pp.97-105.
- Fernandez, A.M.V., Pluim, B.M. & Pearce, A.J. (2006). Intensity of tennis match play. British journal of sports medicine, 40 pp.387-391.
- Harrison, A. and Thompson, K. (2005) Ergogenic aids: sodium bicarbonate. Peak Performance, 219 pp.9-10.
- Kovacs, M.S. (2007). Tennis physiology: Training the competitive athlete. Sport medicine, 37(3) pp.189-198.
- Sharp, R.L., Costill, D.L., Fink, W.J. & King D.S. (1986). Effects of 8 weeks of bicycle ergometer sprint training on human muscle buffer capacity. International Journal of Sports Medicine, 7(1) pp.13-17.
- Verbitsky, O., Mizrahi, J., Levin, M. and Isakov, E. (1997). Effect of ingested sodium bicarbonate on muscle force, fatigue, and recovery. Journal of Applied Physiology, 83 pp.333-337.