Do you experience wild weight fluctuations?

Hi All,
It’s becoming normal for me to gain 2-3lbs (I’m 145lbs) after a big day on the bike…… It makes it hard to track weight and nutrition. Specially if there’s a long block…

Are you guys experiencing the same?

Chat GPT seems to nail it here:

*Yes, those weight fluctuations are common and tied to several physiological factors, particularly in the context of endurance training and carbohydrate consumption:

  1. Glycogen Storage and Water Retention

    • After high-stress biking sessions, your body replenishes glycogen stores in your muscles and liver.
    • Each gram of glycogen binds to approximately 3 grams of water, causing temporary weight gain. For an endurance athlete, glycogen stores can hold up to 500 grams, leading to 1-3 pounds of water weight.

  2. Inflammation and Fluid Retention

    • Intense exercise causes muscle microtrauma, triggering an inflammatory response.
    • This leads to localized fluid retention as part of the healing process, adding temporary weight.

  3. Carbohydrate Consumption

    • If you consume more carbohydrates (e.g., during and after your sessions), this further boosts glycogen and water storage, amplifying the effect.

  4. Sodium and Electrolytes

    • Sports drinks, gels, and post-ride meals often contain sodium, which can increase fluid retention as your body balances electrolyte levels.

  5. Gut Content

    • Increased food and fluid intake around your rides can lead to temporary weight gain simply due to the added volume in your digestive system.*

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I’ve had that happen sometimes, but it’s usually dependent on what I’m eating after that big day on the bike. For example if I end up eating high sodium foods and combine that with beer, then I’ll definitely get that second day bloat response but it usually goes away in another day or two.

My question to you is what is the difficulty you are experiencing in tracking weight and nutrition?

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2 to 3 lbs is not a wild fluctuation. It’s normal.

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1kg of weight fluctuation is completely normal.

You cannot really look at day to day changes, it must be done by looking at overall trends. How does it look like over the last weeks/months?

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Sometimes it lasts more than 1 week. So Idk if I gained that weight for real and I fucked up something with my nutrition

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Seems like chatgpt answered it for you. It seems correct from my understanding. And yes I also do that and seems normal.

I get this too and it lasts so long I have to stop looking at the scale or I’ll be tempted to cut calories and it’s an unproductive loop. I can also lose 8-10lbs on a long and/or hot ride so… yeah my weight is all over the place. Supplementing a lot more salt has actually been one of the biggest performance boosters for me this year, but it definitely leads to long term water storage lol.

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145 to 150

Over what time period? 2kg in one week is a lot different than 2kg over 2 months.

Depending on what your training looks like that could be expected or desired especially if you are doing a lot of gym work. otherwise a small cutback in calorie intake would allow that to reset if that is what your goal is.

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Want to experience some wild fluctuations? Weigh yourself multiple times a day, crazy swings. Really puts weight in perspective.

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I experience the same weight swings. Have seen the trend leading up to races and what happens after races. I can have a 4/5kg swing over 3/4 days.

Usually the Thursday I am at my lowest. By Saturday post race or Sunday morning I am my heaviest. By Tuesday it has resolved back to my goal weight.

I get concerned when I have back to back race weekends as the second weekend race is usually heavier than I like to be.

Fridays and Saturdays it is usually around 1000g carb consumption each day.

Looking at my 6 monthly trend, I am averaging where I want to be.

Have learnt to accept these fluctuations and not get into the weeds too much with them. However, if there is a break from racing, I am back on the horse and fairly level with weight trend.

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Have you tried calculating at 7 day rolling average and tracking that instead of or as well as?

The daily fluctuations may melt away.

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That and for me certain foods. Whenever I eat ramen, I typically gain 1.0–1.2 kg. But since I promptly lose them again, I don’t worry. With other foods I “temporarily lose weight”, and it’d go back up.

My solution is to really just look at weekly averages of weight as an indicator.

I am seeing even bigger swings at 68kg. It is why I only really pay attention to what my scale says after getting up on well rested days, everything else is skewed by varying levels of hydration, glycogen stores and gut content.

Those aren’t wild, they are normal. Truly wild fluctuations (usually losses) would be worrying but 2-3lbs is not!

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Absolutely normal.

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What’s a big day on the bike and how does that differ from what you normally do, and what is different about the fueling? Is it like 3,4,5,6+ hours and 4,000 + calories? For fuel, is it like 100 grams per hour? And how are you taking in this fuel?

While 5 lbs isn’t that much, it’s not that little either, but if it takes more than a week, then that seems like more than what would be expected. If you feel good otherwise, then I’d be tempted to accept it. If you feel bad, then I’d look at possibly eliminating and/or replacing something in your fueling during the ride, or for you post ride recovery meal.

This is totally normal for me within one day. I have weighed within my current weight range for over 20 years. I’m not sure how people set their weight for calculating w/kg based on how much i fluctuate during the day ( I settled on just using my typical weight during a ride - average of pre-ride and post-ride).

One extreme I had that stands out to me was going for a morning long run in the heat and when I finished I weighed in much lighter than I expected, by the end of the day however I was up 10-11lbs from my post run weigh in.

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Fwiw I really like Happy Scale an app I use on my iphone. It has different averaging algorithms you can use and a good interface to see rolling change of weight over time. It’s really helped me see change of time vs day to day which can be hard to see trends.

I experience wild fluctuations over long periods (weeks) where I will gain or lose weight kinda uncontrollably. I think it’s tied to stress, peaking, sleep, etc. This past Sept to October I went from 183lbs to 190lbs, correlated to peaking for Leadville in August and then reducing volume when I got back home. 7 lbs is a lot! I’m back down to 185-186lbs and happier. It was scary when I thought I was going to 200lbs uncontrollably.