Paul Balsom, Head of Sports Science and Performance Analysis at 2016 Premier League champions Leicester City, first started measuring heart rate to monitor load in the 1980s and was one of the first sports scientists in the world to use first-generation 1 Hz GPSports devices in the early 2000s.
Returning to Northeast Asia for the first time since the 2002 FIFA World Cup, Paul spoke at our Japanese and Korean workshops last week in front of over 130 performance coaches. Speaking about the value practitioners can derive from tracking technologies, Paul hammered home three key takeaway points from the start:
- There are three kinds of physical fatigue in team sports that can affect performance, not including mental fatigue.
- Technology doesn’t make decisions; people make decisions. There’s always been a focus on recruiting the best players, but now the best teams are focusing on recruiting the best staff.
- Player tracking is an important tool for monitoring load and load management is a key element of improving performance capacity and reducing injuries which saves clubs money and increases the chance of success.
The difference between winning and losing is getting smaller, but the ramifications for both are getting bigger. With the stakes getting higher, sports scientists can benefit by better understanding the value they’re getting from player tracking technologies.
Sports science and the ability to monitor elite athletes is not new. Researchers were monitoring heart rate and blood lactate in the 1960s and 70s to get a better understanding of how hard athletes were working, but now sports scientists have a wide range of tools, of which player tracking devices are one of the most important.
So how does sports science help football teams win, Paul asks? Through two clear benefits:
- Reducing injuries
- Improving performance capacity
Evaluating physical performance in team sports is extremely complex, but measuring and understanding the performance capacity of your athletes is vital, especially for load management and identifying an optimal load to prevent under- or over-training. But as Paul repeats: “Player tracking doesn’t manage load, it measures load.”
Three Types of Fatigue
Player tracking is a great tool for educating coaches, players, and sports scientists. We get approximately five hundred thousand data points per player in a match, so we need to understand what we’re looking for.
One of the most significant findings from Paul’s PhD dissertation (High Intensity Intermittent Exercise) was that when subjects completed 40 x 15m maximal runs with 30 secs rest between each run there was no significant decrease in performance during the 40 runs. However, when the subjects performed 40m runs 15 times with 30 seconds rest between each run, there was a significant decrease in performance after the first four runs. This explains transient fatigue during team sports, which is defined as “moving in and out of a state of fatigue during training or competition with repeated high intensity efforts in short periods of time.”
In addition to transient fatigue, accumulated fatigue is “what athletes experience towards the end of a session”, and residual fatigue (in between games), shown when an athlete is already tired ahead of your next game, are also important.
In an Australian-based research article, ‘Fatigue Monitoring in High Performance Sport: A Survey of Current Trends‘ (Taylor et al, 2012) the authors concluded that the best way to evaluate residual fatigue is via a so-called wellbeing questionnaire, i.e. by asking the athletes to score how tired they are.
Another type of fatigue is mental fatigue, which Paul predicts will attract more attention in the next five years. Players are making thousands of decisions every game and the importance of every decision is increasing. We don’t yet fully understand the consequences of this and how mental and/or physical fatigue influences decision making especially in periods of transient fatigue and/or towards the end of the game.
Fatigue is complex and player tracking is a vital tool in helping practitioners and players understand the consequences of fatigue on performance during matchplay.
In Major League Baseball in 2016, over $700m was paid in salaries to injured athletes. In the Premier League. it was over $300m. It has been estimated that around 40% of these injuries could be avoided, with load management being a key factor.
When Leicester City won the Premier League in 2016, on average they only had one player not available for selection due to injury in each game (96% player availability). Furthermore, they only used 18 players throughout the season, making them the healthiest team in the league.
One thing that helped influence Leicester City’s injury rates and therefore success on the field was load management. For example, the players often did not train threes prior to each game (matchday minus three, or MD-3). An interesting observation was that this led to a noticeable increase in intensity during training on MD-4 and MD-2.
Another key for Leicester City was “the effective bond created between playing staff, coaching staff and indeed medicine and sports science.” The players were given more responsibility than ever before for their own levels of fitness and wellbeing.
Find out more about Catapult’s performance technology here. For a further insight into the sports science that underpinned Leicester City’s title win, you can watch a recent presentation by Matt Reeves, Leicester’s Head of Fitness and Conditioning, on our YouTube channel.