Fasting and exercise


I am trying to keep the Ember Days fast as suggested by various Catholic leaders and organizations in light of recent challenges the Church is facing (and to be honest, my own spiritual life could always use improvement).

But I am also preparing to run a half marathon in two weeks and had a hard five-mile speed workout yesterday and an 8.5-mile run today that involved some pace training as well. I am a little worried that a lack of fuel combined with hard workouts is a bad combination. Is there any reason to be concerned about fasting under the circumstances?


Do what is best for your physical health for the marathon. You do not want to get weak and pass out during the run.


Thanks for the reply. I already did today’s run. Just thinking about bodily recovery and nutritional needs.


Fruit juices are allowed and provide calories. Might be best to ask a doctor about exercise when doing any religious fasting, though. Generally I just opted out of exercising whenever I did any fasts in the past. This ember week is almost over, is it not?


Fast from something that isn’t food if you’re training. You don’t want to make yourself sick, and this is an optional devotion.

I always feel free to move non-obligatory fast days to another day when I need to drive or exercise.


Yeah, there’s thousands of things to fast from besides food.
Also, a food fast doesn’t need to be all day. Fast for some hours, skipping a meal, for example, but not denying yourself to the point of neglecting your physical health.
Skipping a meal and snacks here and there is beneficial to your health. Healthy fasting.

My $.02


Aerobic exercise which completely depletes your glycogen reserves (aka “hitting the wall”) is not only detrimental to your athletic performance, but can be dangerous. Consult a doctor before distance running while on any low-carb diet.


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