Exercising on a Water Fast

Intervention: Day 6, 140 hours, 324 lbs, BMI 46.5

Exercise has not been my strong suit. Although in some respects it has. Before I went back to university, I used to be fairly active. Scuba, squash, bicycling, hiking and similar type of activities that I would do on a regular basis. Trying to do university and work full time leaves little time to do other pursuits. And things just got worse after that in managing two businesses, both of which are sedentary in terms of physical activity.

This is not to excuse the lack of exercise, it is just to say that it becomes far too easy to lose track over time when you are eating a similar diet to when you are active to be gaining 10-15 lbs per year when you are not active. It creeps up on you and it becomes all too easy to say “well its only 10 lbs – I can lose that easily enough”.

Ya – it is not. Especially when you let things get out of control after 15 years of the same excuse. It is not hard to lose track. Its only 120 cals/dy on average and 100-125-150 lbs of excess weight can build up even if you think you are behaving yourself the majority of the time.

At a certain point, you have to take responsibility and at least try to get back to better habits. That means incorporating some form of exercise into your daily routine.  While I have been trying to do this for months, a water fast I’m thinking is actually a good time to build in this habit. The time you would have spent eating and preparing food can be devoted to other things.

The main challenge from my standpoint isn’t how to build-in activity, it is developing the routine. Building in, not just a commitment to develop a healthy habit, but actually looking forward to doing it. It is retraining yourself to want to be active because it is the path of least resistance. That is hard when so many other things are waiting to compete for your time. Often I find myself being really good about being active for months, only to have something come up that interrupts the routine and back into old patterns we fall.

Water fasting, however, is not the time to be doing a 90x fitness program.

The main goal here is to build up an association with activity (note: not exercise) and feeling good. To make regular activity the ‘path of least resistance’ such that you want and desire to be active rather than feeling you need to be active.

I’ve worked with a number of fitness trainers over the years and they have all missed this one essential point. They will immediately start to work on your body, rather than your mind. For someone with a BMI of between 20-25, that might not be a bad place to start. For people with BMI’s over 30, the body is not the true source of the problem, it is lifestyle.

So my exercise program over the course of the water fast is to accomplish three things

  1. Walk 45 minutes per day as a consistent discrete activity as part of my daily routine;
  2. Planks done frequently throughout the day (core strength – full body);
  3. Move around more often during the workday.


From what I have been reading, trying to do a full workout during a fast is just going to burn you out. While the body has lots of energy, since you don’t have the glycogen stores, nor the carbohydrates, you only have so much to work with before the body needs to start focusing on other sources. Ketones are not enough for rigorous anaerobic exercise but are perfectly suited to low-intensity aerobic exercise.

If the body starts to get into anaerobic mode then it’s going to start hunting for the nearest source of glycogen it can find, and that is muscle mass, not fat. This is not good during a fast because you are not taking in protein and other nutrients to help build new muscle. To build up your VCO2 levels during a fast you want low-intensity, long duration aerobic activities that are not going to drive excessive amounts of lactate.

Similarly, when doing weight training you want to focus on short intensity, low resistance types of activities and space them out. The goal here is not to build new muscle, it is to tone the muscle you already have. Planks are a good core strength exercise that provides overall conditioning. The other nice thing about planks is that there are a lot of variations on how to do a plank for all levels of fitness. You can also introduce other variations such as leg lifts and side planks that can further help tone and condition big muscle groups.

The idea here is that we want to work with the chemicals our bodies are producing naturally as much as possible.

Activity Indoors verses Outdoors
Intervention: 120 Hours Later

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