If you have ever suffered from any kind of over-training syndrome, or know others who have, you will be very keen to avoid it. As endurance athletes we love to train – that’s why we do what we do, so how do we know how much is too much?

Training load (the amount of stress created by your training) is very individual and there are no absolute numbers that work for everyone. But with careful measurement and tracking it is possible to avoid over-training.

There are a few things that I do when working with athletes to make sure we get the training load just right.

For those of you without the luxury of a coach I have listed the main things you can do to avoid over-training and covered in more details in the article:

  • Measure your training load;
  • Take account of your training history;
  • Work from where you are not where you think you should be;
  • Take account of individual factors that increase your overall stress;
  • Take account of the different types of training you do;
  • Do the minimum you need to to make the fitness gains you need;
  • Plan for and take regular easy weeks, rest day and down periods;
  • Monitor for signs of over-training with HEMP (Health, Energy, Mood, Performance); and
  • Be your own personal scientist.

Measure the Training Load.

A key factor in not doing too much is of course knowing how much you are doing…and that’s not as simple as miles or kilometres travelled. Some miles will be faster than others, some will be harder because they are off-road or uphill. If you are a runner and do mainly sessions on the flat then miles can be a good indicator, although this doesn’t account for faster and slower miles.

My own preference with athletes is time; this is how I plan most training and individual sessions because it’s a good catch all, allowing for some sessions to be faster and some to be slower.

However, it’s also a good idea to keep a note of the amount of climb you are doing if you are doing a significant amount of it; you could easily overdo it by simply keeping to the same training durations or distances but increasing the amount of vertical too quickly.

Applications like Strava and TrainingPeaks, help you quantify training by working out the stress or load of each session via the duration the intensity (Intensity Factor) of the session, which can also be helpful. They can then produce charts to show you how much training load you have done in the shorter and longer term and use an algorithm to work out how ‘fatigued’ you are. This can be a helpful, objective guide to help you identify and plan harder and easier periods of training.

Here is a copy of a Performance Management Chart from TrainingPeaks; as you can see, the athlete will be ready for a rest soon as the fatigue has increased substantially in the last 7 days.

Remember the numbers produced are based on an algorithm, they are only as good as what is being put in. In particular, if your training zones, or more particularly training thresholds, are not set correctly in TrainingPeaks it can under or over-estimate the cost of a session.

In addition to this, numbers do not tell the whole story. If for example you did a series of 30 second repeats the overall training stress score would be relatively small, but the actual physiological cost of the session would be high as you would be working at a very high intensity.

Take account of your training history

The greater your history of training and the more volume you have done in that time, the more volume you are able to manage. So, an athlete who is used to training 13+ hours per week is likely to be able to handle more load than someone who has never exceeded 6 hours per week.

However, it’s not as simple as the more training volume you have had the more you can add, in fact the opposite is true, the higher general load you carry the less leverage you have to increase this…I like to think of this as everyone having a limit. So if you typically train 13 hours per week, you will have less ability to add more hours than someone who is typically training 3 hours per week.

Fatigue is cumulative; so, you may be able to support a jump in training load for a week or possibly two but week on week you will get more and more tired until it becomes too much. That’s why it’s possible to do blocks of intensive training, but not to maintain that intensity for long periods. Training Camps can work like this in that you may have a 1 to 2 week block of volume much higher than you are used to, after which you need to recover.

Work from where you are, not where you think you should be

A mistake I commonly see amongst athletes that have burned out is that they simply have tried to keep going at a high volume for too long under the assumption that because they managed it for a two week period they should be able to manage it forever. A knock on from this problem can be that when athletes do take time off to recover they then jump right back in to the same load that broke them before.

A good premise with training is to start from where you are, not where you think you should be. This can be particularly pertinent after a long break as we can assume that we can jump straight back in at the level we left, when the reality is that we have lost fitness and need to work at the fitness level we are at now.

Or perhaps you are recovering from an injury and are impatient to get back to training at full capacity; the reality is you can only work with what you’ve got and if the body you have got is saying ‘no’ you have no choice but to listen to it.

How we respond to training does change as we get older. Joe Friel once wrote that he does the same amount of training that he did in his twenties…it just takes him twice as long to complete it! As we age our muscles lose some of their elasticity and as a result it takes our bodies longer to recover, so having said that training history plays its part in what we can handle training wise, age can mean that we simply need to take longer to do it to give our older muscles more chance to recover.

Take account of the different types of training you do.

Some types of training have more physiological tole than others, for example running – we tend to manage less running hours than cycling hours as there is more damage to the muscles in running and therefore our bodies have to work harder to recover.

So when thinking about training volume in terms of hours, those who only run will not be able (relatively speaking) to do as many hours as those who cycle. This doesn’t mean that we should choose one discipline over another to get more hours in, just know that we can support less of some types of training than others.

As with anything there are no hard and fast rules, it may be that someone who has done only running all their lives and at a very high volume may actually be able to do more running than cycling (at least initially).

Another key component to this is the amount of high intensity you do

For the purpose of this article by high intensity I mean anything above your aerobic threshold (i.e. anything above an intensity at which you can hold a conversation). These sessions have a greater cost and require greater recovery and as a result the more of them you do the less overall volume you can manage.

That’s not to say that these sessions are ‘bad’ they are a great way to make specific fitness gains and are an essential part of a lot of training programmes, but it’s important to get the dose right. Again, as with overall training load to a certain extent what you are used to may dictate how much of this type of training you can take, and what you may be able to manage over a short period (e.g. when you are at your fittest) will not be sustainable longer term.

As with any aspect of your body, response to these sessions is individual, some people take longer to recover than others, so whilst typically two days is advocated from one hard session to another, you may find you need three. Whilst some people seem to be able to support two or even 3 high intensity workouts per week, others can only support one.

The key is to find what works optimally for you so that you can get the most out of the key workouts you do, otherwise, why bother with the workout? All that will happen is you will get gradually more and more tired and you will gain little if any fitness from the hard sessions you do.

Take account of individual factors that increase your overall stress

Life stress counts; it increases the levels of cortisol pumping round our body which inhibits recovery and can make hard sessions in particular impossible. Life will happen whether or not we like it and it’s a good idea to plan your training around your life, not in spite of it.

When working with any athlete I take into account the type of job they have and any other life commitments they might have that could impact on the energy they have left to train. There may be certain aspects of this that are relatively stable and unchanging and others that happen quickly (job loss, death in the family, relationship breakdown, etc.) which mean that we have to modify training to account for the stress in someone’s life.

In addition to this, personality can play a big role in how we experience life stress, what would be unbearably stressful for one person would be energising and exciting to another. When planning training it’s really important to know your own levels of stress resilience not just to training but to life; as a coach it’s my job to find that out so we can plan training accordingly.

Do the minimum you need to to make the fitness gains you need

The key to any good training plan is that it fits both the individual’s capabilities and is designed to help them achieve their key goal(s). The training you do for a series of cross country events will be massively different from what you will do for an ultra-distance event of 24 hours or more. Tailoring your training for your specific race is key to being successful in that event. This might mean that you do not perform optimally in other events (for example if your big ultra endurance race is in September, you are unlikely to perform at your best for the race you do for fun with friends in August).

Once you know what you want to achieve, the next thing is to do the minimum you need to do to perform optimally for that event. The margin between enough and too much is usually quite large so you just need to do enough. Successful athletes and coaches are able to decide what the minimum they need to do is and they do just that and no more.

An example of this might be traditional marathon training in which typically runners and coaches will not plan to do the whole 26 miles in training; they do just enough to prepare for the full 26 miles, whilst knowing that doing the full distance in training may cost more in recovery than could be gained by the session.

Plan for and take regular easy weeks, rest days and down periods.

A good way to guard against over-training is to plan for breaks in your training. In addition to following the hard/easy principle, think about having complete rest days planned in. As fitness isn’t linear and it’s actually when we are resting that our muscles are adapting and we are getting fitter this is as important a part of training as doing the training itself.

In addition to rest days in order to counteract the build up of fatigue week on week, plan in regular easier weeks where you reduce your volume by 50% (or more if you need to). Depending on your preference, you may choose to just go easy on these weeks or keep some high intensity workouts in, but beware of doing more high intensity, especially as you reach the end of your easy period and you start to recover a bit.

After a big event we can often experience a high level of fatigue – an accumulation of training fatigue followed by a reaction to the stress of the event. Depending on the event and how hard you trained for it this can last anything from one week to months. The important thing is to plan for this and take the time you need to recover so that you can re-start when you are ready, fresh and motivated.

Be your own personal scientist and track fatigue levels.

As you can see, there are no hard and fast rules with training and you come to your sport as an individual with individual capacity and needs. It’s therefore really important to be your own personal scientist, keep track of what works for you, what is typically too much and what are some of the personal signs you might notice which should tell you to back off – even if it’s three days before the start of that planned easy week!

So in addition to tracking training load in whichever way you choose (Training Stress, hours, miles, vertical or a mixture) track how you are feeling. Make notes after each session so you can keep a track of how hard it felt (Rate of Perceived Exertion), track your morning resting heart rate or heart rate variability so you get a sense of what is normal for you. Track other personal signs of fatigue – grumpiness, poor concentration, making silly mistakes or just a general (unplanned for) feeling of fatigue.

Signs of over-training

Most important of all, look out for the signs of over-training so that if you fail to notice your day to day symptoms you can stop as soon as you notice you are going over the edge. You can use the acronym HEMP if that helps.

Health – if your general health starts to deteriorate this can be a sign you are over-training. Things to look out for would be a higher than usual instance of infections, injuries or ‘niggles,’ or just general muscle soreness, unusual unplanned for weight loss, unusual thirst (especially at night) or just a general feeling that you on the verge of an infection for weeks at a time. For women loss of your periods is a good indicator that things are not right and you may be putting too much stress on your body.

Energy – lower than normal energy levels for extended periods meaning that you are struggling to get out of bed or do day to day tasks that you would normally find easy; this may in part be due to interrupted sleep which is also a sign of over-training.

Mood – a downward change in mood can be another sign, so unusual low mood, grumpiness and poor motivation to train where normally you would be looking forward to your sessions, poor resilience to setbacks (e.g. spilling your morning coffee feels like the end of the world). Poor concentration can also come with this low mood or a disinterest in other activities outside training.

Performance – a downward change in performance both in and out of training is also a sign that you may be overdoing things. So unusual heart rate readings (unusually high or very unresponsive), an inability to hit your usual power or pace or just a general feeling that training is harder than usual (increase in Rate of Perceived Exertion for the same pace/power). In general poor coordination or unusual clumsiness, forgetfulness can be signs outside training that you are under too much stress.

If you are worried about your training and not sure if you are overdoing it, why not fill out this questionnaire and we will give you some individual feedback on what might be going on and how you might improve things?

Clare Pearson
Post by Clare Pearson
December 14, 2022
A professional endurance coach since 2018, Clare Pearson has worked with endurance cyclists and runners to help them achieve their goals. Clare specialises in endurance events, she loves to work with people to help them succeed at their own goals; whether that's a personal best, a completion, a podium or better emotional health. Clare will work with you to design a plan that fits in with your day to day life and helps you get the most out of each session.