Repeat sprint ability is defined as a sequence of a minimum of 3 sprints with an average rest of <21 s between sprints. This occurs frequently in Field Hockey owing to the nature of the sport, with forwards typically required to perform a higher relative workload of sprint distance when compared with other positions.
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Significance
This quality is highly important in a game like Field Hockey where the ability to accelerate and decelerate repeatedly at high intensity is a key physical determinant. By gaining insight into an athlete’s repeat sprint ability profile, we can provide specific interventions to target this quality. However, it is advisable to consider the athlete’s overall running profile including maximal linear sprint speed, max aerobic speed (MAS), critical speed and change of direction ability too to further develop performance impacting insights.
I have previously spoken about adopting a hierarchy of needs approach to field hockey . In this article I outline why it may be smart to focus on minimising the downside before concerning ourselves with the performance upside of maximising an athlete’s repeatability.
Assessment
A 6 x 30m sprint test is a reliable measure of repeat sprint ability, whereby athletes sprint 30m on a rolling clock every 25-30s. Once the first effort has been completed, the athlete has the remaining time on the rolling clock to recover before completing the next effort.
Time per effort (s), total time (s), mean time (s) and percentage decrement (%) are typically taken as metrics to provide insight into an athlete’s sprint profile.
Total time (s) is a reliable measure of repeat sprint ability, which is where we take the sum of all of the sprint bouts that an athlete performs. For example, if an athlete performed sprints of 6.5s, 7s, 7s, 7.5s, 7.5s and 8s, the total time score would be 43.5 seconds.
Contributing factors
Repeat sprint ability can be broken down into initial sprint time and recovery between efforts. Initial sprint time is underpinned by physical qualities such as max strength (peak force production), reactive strength (rate of force production) and lower body power (relative power per kg bodyweight). Recovery between efforts is therefore underpinned by aerobic capacity and lactate buffering capabilities.
Challenges of repeat sprint ability
One of the challenges with prescription of repeat sprint ability is the nature of the quality itself. Let’s take two athletes, called Athlete A and Athlete B.
Athlete A possesses fantastic initial sprint ability but fatigues very quickly and therefore has a fatigue index score (difference between initial and slowest sprint effort) of 8%.
Athlete B possesses a slow initial sprint time but can maintain their velocity more consistently and therefore only has a fatigue index of 3.5%.
Which athlete has better repeat sprint ability?
On face value the fatigue index would suggest that Athlete B has a better repeat sprint ability profile. However, when we look at their profiles side by side we can see the reality of the situation. Not only is Athlete A faster on their initial sprint (and so would smoke them in a foot race when fresh), but is also faster than Athlete B on their sixth sprint. Therefore not only is Athlete A the faster sprinter, but they can also maintain a higher absolute sprint speed across the subsequent bouts, even if their relative sprint percentage is lower when compared with their maximal possible sprint speed.
This highlights the complexity of repeat sprint ability and how it can be easy to fall into traps when comparing one athlete to another. We must take into account not only their relative percentage change, but also their absolute values, with total sprint time being the most reliable measure of repeat sprint ability as has already been outlined.
Developing a repeat sprint profile
Once we have established an athlete’s initial sprint time and their subsequent efforts, we can build a picture of their sprint profile. Putting athletes into one of four quadrants can be a helpful exercise to visualise where they sit relative to either defined norms or when comparing with other athletes in the squad.
N.B. benchmark times need to be relative to the age, training experience and gender of the demographic you are working with.
1. Fast initial sprint time, fast total sprint time
2. Fast initial sprint time, slow total sprint time
3. Slow initial sprint time, fast total sprint time
4. Slow initial sprint time, slow total sprint time
The biggest predictor of total sprint time is the athlete’s maximal sprint speed, as this is their physical ‘ceiling’. The higher the athlete’s maximal outputs, the greater their potential for subsequent sprint bouts. This is why you will often see the fastest athletes in a squad of hockey players performing well in repeat sprint ability too – their fast sprint speed means that they can achieve higher repeated sprint bouts at relatively lower physiological cost.
With that in mind, once athlete’s have been put into one of the four quadrants outlined, we can then begin to develop bespoke interventions for each athlete that address their individual need.
If an athlete is in group 1 , then they are already performing well and keeping them healthy, injury free and on the pitch as much as possible is likely a KPI for them as they have a high value! This may also provide an opportunity to spend more time developing the technical and tactical qualities which are bigger predictors of success in a tactically determined sport like field hockey.
If an athlete is in group 2 , then they are dropping off in their subsequent efforts which is hindering their ability to produce repeated sprint efforts. As we already know, aerobic capacity and lactate buffering are underpinning factors in determining recovery between efforts. If their aerobic capacity has already been ticked off based on a time trial or 30-15IFT assessment, then it may well be that some specific interventions around lactate conditioning may well contribute to improved repeat sprint performance.
If an athlete is in group 3 , which is likely the least common profile to come across, then developing maximal sprint speed is the key physical outcome, and this is likely the same for a slow athlete in group 4 . As we’ve outlined already, the ability to produce successive sprint bouts is heavily predicted by our maximal sprint speed, so developing this quality is vital if we are to improve the athlete’s overall sprint profile.
Programming implications
The implications for this are numerous. Firstly, understanding an athlete’s physical capabilities relative to the demands of hockey is a cornerstone of effective Strength-Conditioning. Once this is understood, we are more able to provide accurate interventions which impact performance and bridge the gap between their capability and performance needs.
Another implication is that we can build a system that enables individual prescription from a centralised model. If we can outline a range of conditioning sessions which account for all four sprint profiles detailed above, then we can quickly and effectively prescribe training to a large number of athletes. Whether there are 3, 6 or 12 athletes in group 2 the clarity that a repeat sprint ability profile provides enables us to prescribe similar sessions for all of them.
A second order effect of this is that it provides clarity for athletes, coaches and medical staff alike. If everyone is clear around what the individual performance priority is for each athlete, then we can remove ambiguity and provide everyone with a clear, collective message.
Example sessions
The following sessions are not designed to be exhaustive, and instead are designed to give a broad idea of how individual conditioning sessions may look based on a range of repeat sprint profiles. Clearly, far more variables would be included when making decisions around individual prescription, and context is entirely missing from these examples, but it at least gives an indication of roughly how different training content may look based on repeat sprint profile.
Lactate buffering sessions (if in group 2 )
Option 1 – 30 seconds max effort sprint, 10 minutes recovery between efforts
Option 2 – 1 minute high-intensity bike work, 30 seconds recovery between efforts
Max speed sessions (if in groups 3 or 4)
Option 1 – Flying 20m sprints from a rolling 20m start (2-3 minutes rest per effort)
Option 2 – Flying 10m sprints from a rolling start (2 minutes rest per effort)
References
Bishop, S Lawrence, M Spencer. (2003) Predictors of repeated-sprint ability in elite female hockey players, Journal of Science and Medicine in Sport, Volume 6, Issue 2, 199-209, ISSN 1440-2440, https://doi.org/10.1016/S1440-2440(03)80255-4.
Bishop et al. (2015) A needs analysis and testing battery for field hockey. Professional Strength-Conditioning. 36. 15–16.
Gabbett, TJ. GPS analysis of elite women's field hockey training and competition. J Strength Cond Res 24(5): 1321-1324.
McGunness A, Malone S, Petrakos G, Collins K. Physical and Physiological Demands of Elite International Female Field Hockey Players During Competitive Match Play. J Strength Cond Res. 2019 Nov;33(11):3105-3113. doi: 10.1519/JSC.0000000000002158. PMID: 28746245.
Sharma et al (2018) Effects of 6-Week Sprint-Strength and Agility Training on Body Composition, Cardiovascular, and Physiological Parameters of Male Field Hockey Players. Journal of Strength-Conditioning Research. 32. 4. 894–901.
Spencer, M. Fitzsimons, B. Dawson, D. Bishop, C. Goodman. (2006) Reliability of a repeated-sprint test for field-hockey, Journal of Science and Medicine in Sport, Volume 9, Issues 1–2, Pages 181-184, ISSN 1440-2440, https://doi.org/10.1016/j.jsams.2005.05.001.
Spencer M, Lawrence S Rechichi C, Bishop D, Dawson B, Goodman C. (2004). Time-motion analysis of elite field hockey, with special reference to repeated-sprint activity. Journal of sports sciences. 22. 843-50. 10.1080/02640410410001716715.