Wednesday, February 9, 2011

Training Load: what is it, why is it important

Training Load: What is it, why is it important

                Training Load is a term Polar uses to describe the cumulative amount of stress placed on an individual from a single workout or over a period of time.  Below is Polar’s own definition of Training Load (aka exertion factor).  
To give you some of my own experience as to the relevance of monitoring training load both on a daily basis as well as over the course of time let me present the following 2 cases. 
Case1:  How much is too much?  Pre-season is always physically demanding. There are still so many fallacies that are commonly accepted in team training, like “you have to break them down before you can build them up”. It also doesn’t help that most coaches still view physical conditioning as a tool for creating mental toughness which really precipitates the physical training be as difficult as possible.  We still hear from coaches when talking about conditioning, “kill ‘em” . . . well guess what… read the papers… we can.  Stepping down from the soap box, the first question becomes how much is too much.  We measured training load over the course of pre-season several years ago.  During this time I was still gathering data and not necessarily using it to guide training as I do now.  I remember we had 2 Israeli players this year and that after the first week of practice, they came to me and said, “coach, my legs feel like stone”.  I took a look at our training load numbers since the start of pre-season 4 days earlier and found that on average our players had cumulative training loads of around 2400 points.  OK, sounds like this could be high . . . having been able to previously measure training load numbers for an actual soccer game I knew that average game training loads were around 350 points.  This means that over the course of the first four days of pre-season the players had played an average of almost 7 games!!!  Btw, that’s way too much.

Case 2: Cumulative Loading.  Sometimes the training load numbers don’t always jump out at you like they did for me in case 1.  Sometimes they happen over an extended period of time.  Take 2 players we had several years back, one a defensive midfielder, the other an outside back; both critical pieces to our team.  During any given session, they may have been toward the high end of the training load range for our team, but seldom was it beyond 1 standard deviation from the group.  Toward the end of the season, it became obvious that both of these players were not performing to their potential.  Both indicated feeling fatigued and somewhat apathetic.  Going back and reviewing their cumulative training load numbers up to that point in the season, I found that there was a difference of about 4,200 points between their totals and the average total for the team.  This is the equivalent of having played about 12 additional games over the same time period. 
Since these cases, I have made changes in the way I monitor and provide feedback to our coaches about the difficulty and intensity of training sessions. 
First, I have become more rigid on training session duration.  While we can adjust the difficulty of drills within the training session to potentially create a more intense session, or a less intense session, one thing I have found is that soccer pretty much looks the same no matter how much you change the manipulative variables of field dimensions, number of players, restrictions, etc.  I do not recommend going over 90 minutes with any single training session.  If it takes longer than 90 minutes, look at what you’re doing and how to do it more efficiently.
Second, I monitor the weekly cumulative load of each of our players.  Some players may need additional fitness, as they did not get enough of a stimulus during the week. *I’ll talk more on this one later, this is a pretty big topic to cover here. Other players may need more recovery time, we try to reserve 1 day a week of our training as a day to balance the training loads for our players. 


  1. Still no fully clear on training load...

    How are "exertion factors" defined ?

    It reminds me of the "trimps", a measure that has been published in peer-reviewed scientific journals, where intensity is time x (HR-HRrest)/(HRmax - HRrest) x k

    where k = 0.64^(1.92 * (HR - HRrest)/(HRmax - HRrest)...

    Is it the same ?



    1. How are "exertion factors" defined ?

  2. The best method for calculating training load and detecting overtraining is the session RPE method developed by Dr Carl Foster in the 90's. Unlike Polar's, session RPE method validity has been demonstrated by many peer-reviewed publications and it is use by many top performing football clubs.

    See more info on: and


  3. Ok. I thought you were referring to something on my site that I clearly don't have

    Analyst Training