07 Oct How to handle the data-tsunami
Football and field hockey are intermittent sports: high-speed actions and short explosive actions are followed by periods of (relative) rest. When monitoring a team, it is important that you get an overview of all these different kind of actions. However, if you want to get an overview of all these actions, it is easy to get lost in the data. The trick is to select a limited number of variables which will give you an overview of the load of the most important aspects. Therefore, it is interesting to know which parameters are used to monitor these aspects.
When preparing your team for the challenging demands of the match, there are roughly four aspects which are the most important: the volume of the match, the high-speed running demands, the demands of the short explosive actions, and whether (and for how long) the player is pushed to his/her maximum. If you monitor your team only on the high-speed running demands, you might miss that your players are insufficiently prepared for the demands of short explosive actions. Hence, it is important to know which variables measure the demands of these actions to know which variables you need to monitor.
The volume of a match is measured with the total distance that the players cover during a match. The high-speed running demands are measured with the distances covered in the different speed zones. Especially the sprint distance (>20km/h) and high intensity sprint distance (>25km/h) are relevant for this case. However, short explosive actions do often not result in a high speed, therefore, load of these actions will not be captured with the distances covered in the different speed zones. Instead, accelerations and decelerations are more appropriate to measure the load of these actions. The last aspect, whether the players are pushed to their maximum (and for how long), can be measured with the time in the fifth heart rate zone (>90% of the maximal heart rate).
The advantage of monitoring these variables is that changing the field size of exercises will result in changes in these variables. Exercises with large field sizes result in more distances covered and more (high-intensity) sprint distance. In contrast, exercises with smaller field dimensions will result in more accelerations and decelerations and more time in the fifth heart rate zone. If you see that your team is not sufficiently prepared for the demands of the match on any of these variables (or does not reach the benchmark), changing the field dimensions of exercises is one of the manners you will prepare your players for a different aspect of the game.
When monitoring your team with GPS and heart rate, it is easy to get lost in the data. Therefore, you need to select a few variables which represent the most important aspects: volume of the match, high-speed demands, the demands of short explosive actions, and whether a player is pushed to his/her maximum. The variables which are most suitable to cover these aspects are total distance, sprint distance, high intensity sprint distance, accelerations/decelerations and the time in the fifth heart rate zone. If your team is insufficiently prepared for the match demands or does not reach the benchmark for any of these variables, changing the field size of the exercises will help you to prepare your team for these demands.