Do you know the feeling when you cannot keep your eyes open an hour after a tough swim session no matter how hard you try?
I know it unfortunately. During university, I used to go to class after the morning swim sessions and notice halfway through the class that I was falling asleep.
So far I was convinced the early starts were the reason of the tiredness, but I recently read an article written by Samantha McGlone who examined the issue from a scientific point of view.
As an Olympic triathlete, McGlone often experienced feeling more fatigue after a morning swim session than after a hard run session. This raised her interest and she started researching in the area to find out about the reasons.
It seems that the most important factor influencing fatigue is the cold water – meaning the roughly 27 Celsius pool temperature. It may not seem cold for many, but if you think about the normal body temperature of 36-37 Celsius, the difference is quite significant. During an hour (or more) long session, this reduces the inner temperature of the body and because humans are designed to keep our body at the same temperature, it will start heating up itself. This has the same effect as lying in front of the fireplace or drinking a nice hot chocolate while watching the TV – it makes us a little sleepy. Since we cannot influence this effect, we can work on counterbalance the effects. Samantha suggests an easy 15-20 minute jog or cycle after swimming to stimulate the blood circulation and heat up the body.
Some people also argue that swimming in open pools in the sunshine can also affect how we feel after a session. From your own experience, have you ever felt that after spending a lot of time in the sun, your times are not as good as normally? Studies have shown that being exposed to sunshine for a long period has a negative effect on the cognitive functions. If we still want to do our swim sessions in an open pool, the best times are early morning or late afternoon.
Sometimes, the intensity of the training sessions can also affect how we feel after them. It may seem contradictory but we can feel much more energized after a very tough sessions. This is thanks to the increased oxygen consumption of the body post exercise. Basically, our body generates extra energy to recover the muscles and allow the body to relax after, for example, this is what we feel after very tough or long races when we cannot sleep well. This post exercise process can take from 30 minutes to a whole day, so it’s worth to use this to our benefit leaving the long, low intensity sessions for the weekend when we have time to recover and doing the fast, intense sessions in the morning.
Finally, the timing of meals is also an influencing factor for the post swim tiredness. Since the morning swim sessions usually start very early, many athletes don’t eat anything before the sessions. Thanks to this, we usually have a huge breakfast after the sessions to refill the body and then the very well-known food coma hits in. To avoid this feeling, you can try and eat something before the sessions and refill with more protein rather than carbs after because carbs increases the food coma effect. Besides, we can try leaving the first cup of coffee until after the swim session, since the workout will probably stimulate the body enough anyway. Then, we can drink our well-earned coffee, but pay attention to consume it in portions rather than taking a huge amount once.
I believe the morning swim sessions will remain an essential part of the training schedule, but paying attention to these little details can help us spending our mornings less sleepy.