Fitness Coach Antonio Del Fosco shares his experience on how he used gpexe to monitor the athletic performance of Empoli Calcio’s player, controlling the workload in a very detailed manner, not obtainable with the heart rate alone.

1) How often do you utilise gpexe?

Empoli Calcio provided me with the gpexe pro system: I am lucky enough to have a device for each athlete, which I utilize daily. The pre-match (a quite standard session I monitored a few times and I now consider constant) is excluded from the weekly load program.

The gym power session is obviously excluded as well. I also use gpexe during matches and everyone wears a device without any problem.

2) Which parameters supplied by gpexe are you particularly interested in and why?

The “hoards of data” which gpexe supplies are selected in relation to the objective of my exercise, session and/or match, to estimate the training load in the most appropriate manner. Distance, Total Energy and Average Power are always part of my evaluations, in that they allow me to easily quantify the load that the athlete sustains in the period in consideration.

These values are evaluated for all players and, on the basis of a simple comparison, we decide whether to increase or decrease the workload. Other parameters like eccentric index, equivalent distance and power event characteristics, are the most considered ones during the power training sessions and especially during the official matches.

3) What type of feedback do you gain from the parameters of interest?

I keep track of the trends of those parameters, for both the team and the single athlete. After a  4-6 weeks period, if I notice that the data is fairly homogeneous, I try to define for each athlete the “individual performance model” and, consequently, also the one for the position. This concept is applied to the data obtained during the training sessions, during particular exercises usually repeated in time (like those aiming at a better condition and technical-tactical goals), but mostly for the matches.

The performance is analysed as a function of these reference points: if an exercise reflects or comes close to the reference parameters, we deem it to be more efficient. If the values obtained during the match are close to or superior to the ones observed beforehand, we continue to “move the end-post upwards”, therefore updating our reference points.

“the gpexe instead allows me to have more complete control of the training load,
with detail I could not obtain with the cardiac frequency alone”

Antonio Del Fosco
Empoli Calcio Fitness Coach

4) In what way does the monitoring of the data impact on the planning of your work?

Once we have downloaded the data and analysed the work carried out, we verify whether the scheduled targets have been achieved by all players. The said evaluation is shared with the coach and at this moment the GPS system “impacts” on the programming of the subsequent session. The parameter which I consider the most important to manage the programming is the energy consumption during the first training session after a match, which should be on average around 24 kJ⋅kg-¹, and which reaches a value of about 103 kJ⋅kg-¹ on the second to last day before the next match. For the first 3 days of training, we maintain an average power reference of about 8 W⋅kg-1, with maximum peaks of 9.3 W⋅kg-¹ and minimum values of 6.5 W⋅kg-¹.

Clearly, the value varies depending on the type of exercise and the dimensions of the pitch. We fine-tune the condition and technical tactic loads using these parameters. Attention is also given to the Mechanical Analysis (particularly eccentric load), on the number of Accelerations and Decelerations, to be verified based on the objectives and the exercises proposed by the coach. The strategies which we use to fine-tune the work loads mostly involve the variations of the size of the pitches and the number of players, by obviously balancing the duration of the exercises and the recovery times. In this way we try and achieve the programmed load as best as possible.

5) Do you use the live and for which purpose?

The live is a very useful tool to schedule session loads. It allows me to visualise the programmed targets in real-time and to create sessions directly on the pitch (inserting athletes and attributing a category to the exercise is a simple operation). I have the possibility to stimulate the athletes or decide to stop the session as soon as the programmed load is reached.

Lastly, an aspect not to be ignored is relative to the time dedicated to the management of the session: I manage to slightly reduce the work period after training, be it to file the data, be it to select the relative tracks, using this acquired spare time to analyze the athletes’ performance and evaluate the session quality.

6) Is there any significant data collected, as an example of analysis, which you can share with us?

Yes! I consider the data obtained during the weekly internal match against the Junior sides very interesting. During our traditional weekly workload, the third day is always dedicated to the friendly with the Primavera team: the players were organised to play for about 30-35 minutes each. I consider this session very important because it is used to manage the workloads of the previous days (those who worked little can do more, even for dry runs, and vice-versa). I have set out below the  team’s average values for 10 of these matches (in brackets are the minimum and maximum values):

• Total Distance: 4.26 km (3.39 – 5.03)
• Total Energy: 19.4 kJ⋅kg-¹ (15.5 – 23.1)
• Average Power: 8.8 W⋅kg-¹ (7.5 – 9.7)
• EDI: 13.5 % (12.8 – 14.1)
• Anaerobic Index: 37 % (36 – 38)
• # Accelerations 2.5 m⋅s-²: 10 (8 – 12)
• # Decelerations ≤ -2.5s-²: 16 (14-18)

7) What type of interaction do you have with the coach relative to the data collected?

The data obtained in each session are analysed and communicated to the coach the next day in graphic and/or table format. We comment on the data before each training session.

This is to get a clear idea of what was done, what could be done and what should be done in the subsequent session, to be fine-tuned if necessary.

8) What type of interaction do you have with the player relative to the data collected?

In the beginning, the interaction created with the player is seen as a type of exam, as if someone is “spying” on what the player does on the pitch…..and the initial behaviour is that of indifference (especially for those who use it for the first time). Then, after spontaneously approaching the PC’s screen to understand the scope of these measures, the interest which arises is stimulating for both sides: for myself, a challenge to simplify the information for the player and involve the player in the joint objective of a particular exercise; for the player, to show what he has done and what his level of performance has been over a period of time.

The next step is to evaluate the values achieved by the direct antagonist of his role (competition). Finally, discover the average values achieved by the role players and the team (awareness). This helps the player to understand how he has trained, and perhaps make him aware that sometimes one can push harder. It has often occurred that a player has said to me “….go and look at the GPS because today I shattered it!”, a way of communicating his feeling, which I could have verified through the data, reinforcing the motivation of the player to push at maximum. This for me was an important milestone.

9) How much time do you utilise on average for the operative phase of the system and on the data analysis?

The time taken for the dressing up is really superfluous. It would be silly quantifying it since once you have explained how to put on the vest, how to switch on and insert the device with the correct orientation, the player is absolutely autonomous. The athlete finds the numbered device in the changeroom, positioned inside a container, therefore he knows that he has to wear the device before going onto the pitch. At the end of the session, the player leaves the device switched on and places it into the container. When all the devices have been returned I can download the data.

With 25 devices and 2 USB-keys, it takes between 7-10 minutes to have the data available on the web app. In the meantime, I will have already sent the data of the sessions to the server with the iPad. I will not hide the fact that at the beginning (it is the first season that I utilise a GPS), I invested a lot of time in studying and understanding the data well, data which would have allowed me to analyse the metabolic power: Initially, I dedicated about 4-5 hours to the analysis of the activities.

10) What pushed you to choose gpexe and have you had any experience with other GPS systems, and if so, what differences did you find?

I started using the gpexe system because the company already possessed it. I cannot compare it with other systems because this is my first GPS experience. I can make comparisons with the telemetry for the heart rate, which I used until the previous season. I started 20 years ago with the cardio frequency meter and a wristwatch, which I applied to some player, to then move onto the telemetry 10 years ago. I checked all my athletes’ traces daily. For some exercises (especially for the repetitive dry runs), I had crucial information by seeing that the cardio-circulatory responses diminished with time. I noticed however that these data were incomplete when I used exercises with the ball in open and narrow pitches when I proposed sprint work and power training. This is because the cardiac frequency would not increase, due to the athletes’ technical skills and the brief duration of the exercise.

The gpexe instead allows me to have more complete control of the training load, with detail which I could not obtain with the cardiac frequency alone. I hereby refer to the mechanical component (Eccentric Index) and the instantaneous energy expenditure. The gpexe permits me to interface with my colleagues and have a common language. For example, when the players return to their respective national teams, I receive data on what they have done from my colleagues, which allows me to give continuity to my monitoring, notwithstanding the absence of these players from the team. In this way, it becomes simpler to plan the loads also for these athletes and align them with the team. I have not, however, completely abandoned the old road for the new, I still use both systems (GPS and cardiac frequency).