Water Fasting between sweet spot base phases

I am going to do a 7 day water fast between the two phases of my current high volume sweet spot base plan. I know my power will fall off during the 2nd phase, but I’m good with that. I’m hoping that it will come back to normal or better when I reset my metabolism, liver, and adrenal system. Right now, as a 225lb cat 3, my weight is my enemy. Has anybody ever tried this before and if so, what were your results?

So no food for 7 days? That sounds pretty extreme. I have never done anything like that.

Is your goal to loose weight? As a point of reference- I lost 30 lbs over the course of a year with TrainerRoad and diet improvements. It was a gradual process- but my power kept going up as my weight came down.

It’s not so bad. I’ve done a water fast before. Just wondering if it will have a positive or negative effect on my training as a whole. Should I take an extra week to recover from the fast before starting the 2nd half of SSB?


Not eating for 7 days is going to have a decidedly negative effect on your training.


I would imagine it would set you back at least two weeks but I will have to look into the literature more on water fasts and their affects on the body.

You lose weight in the kitchen and get faster on the bike. No good can come from fasting for 7 days and doing high intensity workouts. You might shed a couple of pounds, but your workouts are going suffer. Even fasting for 24 would be difficult if doing high intensity work.

Focus on the core issue, food quality and quantity, if you can fix that, in conjunction with riding lots, you will solve the problem.

Sounds like a terrible idea to me! You’re more likely to slow your metabolism than ‘reset’ it. You need to think long-term about your diet rather than trying some gimmick. And yes, I imagine your training would take a severe step backwards.


I wouldn’t do that in any circumstances. One needs enrgy to train effectively, and I think, in the end, you will not be able to permanently lose weight with that kinds of things. I’d say that most of it, or even more, weight will be gained when you start eating normally again.

I didn’t realize fasting was a “gimmick”. Last I checked, the Gandhi diet wasn’t very popular. It’s more of a cleanse. Like I said, I’ve done it before, just not while training. I was wondering how it would affect the second phase of my sweet spot base training plan. I’ll be eating by then.

No worries. Thanks for the input.

Check out a guy call Peter Attia, he is a huge self experimenter on himself and a very experienced cyclist/endurance athletes. He is also a TR user I think. Anyhow…I don’t have the specific reference at hand but he recently wrote a blog post and a podcast perhaps on this exact thing having done it himself. Just Google for either of those and you’ll find it. In the meantime if I can locate the exact episodes I’ll post them here for you.

Thank you Tom

Ahhh here you go…

This should get you started, you will find his blog archive fascinating. Be aware though that this often isn’t in ‘layman’ terms so will require some base level understanding



Tom, this is exactly the info I needed. Thanks a million!!!


Reset your metabolism? That’s just pseudoscience.


Omg…its a figure of speech. You can’t reset metabolism.

I listen to all of his podcast he is definitely different in his thinking and is a DR that has done some crazy endurance stuff. He seems to eat so little pretty much daily with intermitted fasting. Depending on what type of riding/ racing you do not sure we could do what he does or did.

Fasting is a topic on its own. And its a whole other topic if it comes with endurance sports.

By the way: whats up with you in the US and water fasting? So many people are talking about it. From my european point of view it looks like another Silicon Valley optimizing your body approach.

But back to the top: I did not a water fast but a week of FMD (Dr Valter Longo). I read the book and did it for health reasons. It was my recovery week and and I went really slow. But it was no problem. The week after I started my training as always. But the FMD endet on Friday so I could eat three days my regular food.

( I really can recommend the book by Valter Longo. And even if it looks like you have to buy some things. Thats not the case. Just in case your are not willing to calculate your food and have to much money. Than you can order his boxes. )

All the best for your fast!

True, he will say himself that he would never recommend what he does to someone else.

You could fast for 7 days drinking only water, lose weight (probably end up not being the weight you want to lose) and pretty much lose the capacity to train on the bike putting your fitness back aswell


You could eat a balanced whole food diet, with a sufficient macronutrient spread at a 20% calorie deficit to lose weight and also still have the capacity to train/even gain fitness.

I know which one I’d choose.