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How to mix up your pace when running?

You love running, don't you? So, over the course of your running outings, you get caught up in it and this leads you to run for longer and at a faster pace. You feel better and your times are improving week on week, until you reach a point where you feel you are stagnating. One of the keys to resolving this problem may be to change the content of your training sessions: have you thought about mixing up the pace at which you run?


How does the human body generate the energy it needs?

Whatever the physical activity, the body needs energy to do it. This energy, which can be used by the human body, is called "ATP" and it is present in tiny quantities in our bodies. So the only challenge is to continually create ATP.This can be done in 3 ways and these 3 ways are called "energy systems":

- the Anaerobic Alactic systema very large quantity of energy per second for a very short period of time (7 to 10 seconds);

- the Anaerobic Lactic systema intermediate quantity of energy per second for an intermediate period of time (1 to 5 minutes);

- the Aerobic systema low quantity of energy produced per second albeit for a very long period of time (several minutes to several days).

This is what makes it possible to run races lasting between several seconds (60 m, 100 m, etc.) and several hours or days (marathon, ultra-trail run, etc.)


Why mix up different paces?

But the human body's primary aim is self-preservation. It will therefore always adapt so that, for any given level of physical exertion, it makes the least possible effort. When you got back into running, you felt out of breath and sweated a lot after your first session. You felt as if you had pushed your body to the limit. As you continued running at comparable speeds, you gradually felt better. This is because your body adapted to the demands put on it and acquired physiological resources to respond more effectively to the effort required on a regular basis. Once a balance has been reached between improving your capabilities and the ability to cope with the repeated demands of your training sessions, the human body will stop improving its capabilities.

In practical terms, what does this mean? Take, for example, a runner who runs at a pace of 10 km/h. Initially, he will find it difficult at times, but if he perseveres, he will gradually feel better: after a few weeks, still at a pace of 10 km/h, the breathlessness or pain will diminish. However, if he continues to run at the same pace, his average speed will not improve. Why? This is because he is only using one of the 3 energy systems mentioned above, i.e. the Aerobic system. So that the body can continue to develop and improve its different running paces, runners must mix them up and make use of the other 2 energy systems.


How do you mix up your running paces?

Monotony is the enemy of the human body, both for your muscles and for your morale. That's why it's important to mix up the paces at which you run and the demands you place on the body. The training plans proposed by coaches will incorporate these different forms of exercise. However, if you wish to put together your own training plan you must be aware of a few rules.

- variations throughout the year: road runners aiming to run a marathon may set themselves intermediate objectives over 10 km and/or the half marathon distance. These objectives will help to improve speed and work on a pace specifically tailored to running the marathon. Your annual plan is therefore important.

- variations in the training plan: a training plan generally lasts between 8 and 16 weeks and will be composed of different cycles. Each training cycle (a cycle lasts 3 to 4 weeks in most cases) will have a different objective and will create a balance between the exercises focused on the different systems needed to reach your final objective.

- variations during the week: a short run with some technical work, sessions run at a specific pace, long runs, cross-training (swimming, cycling, rollerskating, cross-country skiing, weight training, etc.): training plan weeks are always composed of different types of exercises. This is what gives a pattern to your week and helps to motivate you on a daily basis.

- variations during the session: the most well-known method for varying the pace during a session is the so-called "Fartlek" interval training method. During this type of session, you accelerate at will and according to how you feel for sections of varying length. Although this type of session is a bit more demanding than a simple run, it is not quite as inflexible as a training session involving threshold levels or VO2max levels and will brighten up your week. Whatever the case, properly planning your session (warm-up at jogging pace, specific exercises, recovery at jogging pace, stretching) is essential for exercising the different energy systems.


As you will have realised, mixing up the paces of which you run is an important factor in your training. If you do not feel comfortable setting your own running paces, the heart rate or, very simply, your breathing can guide you in finding the right pace. Now it's over to you!