What Happens When We Stop Training?—with Dr. Iñigo Mujika

We explore what happens to our bodies when we stop training for a period of time and address how to successfully navigate the effects of detraining.

Sporty muscular african male athlete in earphones looking away, stretching legs while sitting at the stadium race track
Photo: Shutterstock

If you ask endurance athletes—of all abilities—their greatest fears, somewhere near the top of their list will likely be “losing my fitness.” Whether it’s a planned off-season break, a family trip, or being sidelined with sickness or injury, endurance athletes dread watching all their hard work slip away. It can sometimes feel like your fitness is vanishing fast—and in some cases, that’s actually what’s happening. Blood volume drops quickly, and within four to five days your VO2max begins to slip. For new athletes, all of their gains after months of training can disappear in a matter of weeks.

Fortunately, it’s not all bad news. None of the immediate detraining effects are structural, meaning you can get them back relatively quickly. And for lifelong athletes, the longer-term structural adaptations never fully go away.

In this episode, we talk with well-known physiologist Dr. Iñigo Mujika, who is recognized as one of the world’s top experts on detraining, which he has defined as the physiological result of reduced training.

Along with Dr Mujika, we talk with legendary coach Joe Friel, coach and physiologist Adam St Pierre, and World Tour pro Toms Skujins, all of whom share with us their thoughts on navigating the off-season.

So, take a break, and make it beneficial—and let’s make you fast!


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Episode Transcript

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