Part one of this series looked at the key benefits and differences between electronic performance and tracking systems (EPTS). For this second instalment, our journey into player performance takes us to a crossroad where condition, workload and tactics intersect.
In the industry condition is also referred to as internal load and deals mainly with the work of the heart – heart rate (HR) averages and maximums, times spent in the different heart rate zones (recovery, aerobic, mixed, anaerobic, lactic). Workload, also called external load, covers parameters like distance, speed, distance in the different speed zones, sprints, accelerations, decelerations, changes of directions. And while you can track the latter with an optical system, you need a wearable electronic performance tracking system for the former.
As core parameters, both condition and workload tracking have been available for quite some time now. Heart rate monitors of varying quality have been around for over 20 years, while video recording is practically a staple in every club and at all age levels. The next level has been turning these basic parameters mentioned above into higher-level indicators and insights.
Instead of simply tracking time spent in each HR zone, we combine through an algorithm into Heart Exertion, Recovery time and Recovery beats. And all the various workload parameters, which are hard to observe in real time, are pooled and enhanced to Total Energy Expenditure (TEE), High Metabolic Load Distance (HMLD).
Additional indicators, such as Equivalent Distance, Metabolic Power and Intensity Indicator, can give more granular understanding without the need to go into the raw parameters. And ultimately everything is combined through a Work-Load Index, which gives the ratio between the External Load and the Internal Load – i.e. the physiological stress experience by the athlete during training compared to the work done.
But what is the meaning of all this? Why do we need to track this in such detail? And what more are the high order indicators and insights giving us compared to the raw parameters?
Total Energy Expenditure summarises the volume of the external load of players, monitoring every small tilt, rotation, direction change, acceleration, deceleration and so on, in the greatest detail. Using team and personalised views with slices, we can see who is pulling the team up or down, whether there is a need to adjust the session load or duration, how balanced the performance is during the match, and if there are any abnormal drops indicating a problem in performance.
Accumulated Heart Exertion is the next big thing to pay attention to during the session. It is an insight for the volume of internal load and monitoring for abnormal deviations is highly recommended. It should be benchmarked and tracked with caution as it is usually also used as an alert and, when combined with Real-time Recovery, it gives a very handy snapshot of the players’ momentary condition (as shown in the chart below).
Taken together, Total Energy Expenditure, Heart Exertion and Recovery can define the duration of a training session, changes in length and intensity of individual exercises, and adjustments to the entire micro-cycle based on daily targets.
Real-time understanding of temporary exhaustion vs heart fatigue is critical as athletes push performance beyond their limits in terms of high-speed or explosive bursts. Correlation between heart rate, speed and metabolic power is crucial and gives insight for momentary condition or a substitution need. Abnormal time spent in players’ individual training zones is also a clue for further monitoring and deep-dive analytics.
Barin Sports’ dashboard is a very powerful instrument for training/match pace change. It gives extremely detailed information for the whole session or the building blocks of it, on an individual and complete team level.
Chart 1: Connecting internal and external load in an easy-to-understand picture: The constant high heart-rate, long time spent in HR zone 5 (lactic) and the lack of changes to HR despite steep changes to speed and Metabolic Power are a sure indicator that this player is fatigued and with a high-chance of non-contact injury due to overwork.
Chart 2: In comparison to Chart 1, this player is in much better condition – the increase in speed is followed by an increase in heart rate (it is normal to have a delay between the speed burst and subsequent spike in heart rate)
Modern football is all about explosiveness. High Metabolic Load Distance (HMLD) has become a highly used metric to define the accumulation of high intensity efforts. HMLD combines information for player load, agility, accumulated explosive moves, and high-speed running in one parameter. Additionally, looking at the ratio between HMLD and Total Distance is a handy metric helping to reduce volume, and increase dynamics – the “train-smart-not-hard” approach.
Significant fluctuation in HMLD during a match is a powerful indicator for conditioning issues, substitution, pace or tactical change. And since it is a cumulative indicator for many parameters it directs you in the “deep dive” to pinpoint where exactly the problems in performance are coming from.
High-speed running (HSR) is usually the metric that suffers the most during the game minute after minute. Being able to measure it at desired intervals means that it can be managed. Trying to balance HSR throughout the game could be very beneficial at the end. Monitoring Top Speed peaks by minute is also a good sign of how well the players are prepared and if they could finish the game in a good enough condition. Max Power is one of our favourite parameters for explosiveness.
Ultimately, the goal is to balance a player’s load during a micro-cycle as it is crucial to ensure they are going fresh into the match.
So far, we have focused on the connection between condition and workload. Their role, however, is in service of the tactical assignments set out by the head coach because, after all, this is what leads to wins.
Too often performance tracking is relegated to the Strength & Conditioning coach with the “simple” instruction to make sure the players are in peak condition for the match. Tactical execution should not be analysed separately but in correlation with performance and current physical condition. This requires real-time, second-by-second monitoring of distance between players, lines height and width; distance between correlated tactical lines; heatmaps; sprint distributions; high-speed efforts orientation (Attacking, Defending, Left or Right); average positions; event-based tactical analyses; and whole team metrics (length and width).
In this way a coach always knows how each player is executing their assigned role (how “free” somebody’s free role is, how fluid the transitions are, etc.), how to control match pace (whether they have enough “juice” for extra press or counter-press, how high the press should be, who can do it most effectively in the exact moment, etc.), when individual limits are reached and how to recover, what the exact fatigue level of every player is before, during and after the match. This has the benefit of improved in-game management where the performance drops are seen immediately and the reasons behind them is known.
Condition, workload and tactics form the three pillars on which the performance success of any sports organisation is built. Often, even in the largest organisations with dedicated analytics teams, they are being analysed separately instead of combined together.
Strength and conditioning coaches focus on the internal and external load during training sessions, while analysts usually review the video footage of matches for tactical analysis. They use different tools and presentation formats for their findings, which poses a challenge in connecting all the performance data streams into a cohesive picture and doing cross-reference analytics to allow coaches to take the most effective and efficient decisions in real-time.
Connecting condition, workload and tactics is merely the beginning in getting a deeper understanding of performance tracking. They form the base of what is to become sport science. And yes, this means that science is more and more becoming an integral and indispensable part of the “art” of football.
To read part one of this series, click here.