Weight loss when cycling

Just curious, if you were trying to lose weight how much of the fat burning goes on during the ride and how much during the repair/recovery period.

i.e. if you weigh yourself before and after a ride its tricky to tell how much of it is from dehydration.

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Not entirely clear on what you’re getting at but, weighing daily while training has not been the best way to monitor trends for me. Way too much variation in blood volume, dehydration, etc…Ideally, I try to take a weight each week, same time during similar training loads.

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Are you asking if the obvious energy usage during exercise continues afterwards?

I’d argue almost the exact opposite.

Weigh yourself ever day, but look at general trends rather than day-to-day fluctuation.

If there’s “way too much variation” then the key is to take more data points, not fewer

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Only point of weighing yourself before and after a ride is if you’re trying to determine sweat rate (in which case you also need to keep track of how much you drank, and not take a pee…). Any fat you’ve burned during the ride is certainly going to get lost in the noise of hydration and water retention levels.

While trying to lose weight I find the best strategy is to accumulate a calorie deficit on easy and endurance rides. When I’m doing intensity I want enough calories available to do a good quality workout, and when I’m recovering from a hard workout I want enough calories available to ensure I’m recovering and adapting properly to the training stimulus. An example might be a 2 hour Z2 ride like Boarstone which for me is over 1600 calories. I might do the first hour fasted (I.e. first thing in the morning when I’ve had a coffee but nothing to eat), then take on maybe 300 calories in the second hour followed by breakfast afterwards. So I’m heading into the rest of the day with a full stomach and a 5-600 calorie deficit. As long as nobody brings a box of Krispy Kremes into the office I’m all good…

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Weighing before and after (including bottles) is a test for sweat rate, suggesting the weight loss during a workout is predominantly water. I can be 1kg lighter after a 1 hour trainer session, and if that was all fat then that would need 7700 calories to be burned through in that hour.

I use the trainer efforts to ensure I am calorie negative for the day, and go for weight loss that way.

On a long previous podcast I recall @Nate_Pearson saying ‘ounces are lost on the bike, pounds are lost in the kitchen’. This has stuck with me.

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The sensible way to test weightloss is just weigh yourself periodically. So I like to do so every morning, same time to track a 5 day rolling average.

Why?

Because it can really fluctuate due to water.

If you want to lose weight, it’s in the kitchen

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No my point wasnt about weighing myself, I realise this goes up and down daily.

Just how is the fat burnt due to exercise? is it 50/50 Out on the ride/additional calories burnt due to recovery from ride?

I know its something that is out of our control, just curious how long and much the effect of exercise continues to have on your body outside of the effects on muscles.

Old gym adage…“abs are made in the kitchen, not the gym”

The answer here then is… it doesn’t matter.

No really, hear me out. If you only burned glycogen and depleted yourself, for the rest of the day whilst you were sedentary, your body would burn fat for energy. If you burned fat though for your exercise then your body would slowly eat away at your liver glycogen stores on the whole.

What matters is keeping a calorific deficit. Worry about that, and worry about keeping enough glycogen to fuel workouts. The weightloss will take care of itself.

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Its a bit of a how long is a piece of string question.

The zone you ride in obviously affects how many calories you burn per hour.
The “fat burning zone” is pretty much nonsense

I can’t recall the exact figure off hand but at flat out race pace I burn 700-800 calories per hour, but at that pace the majority will come from sugar or glycogen stores so negligible fat burning as such.
Over a longer ride at a slower pace I might expend 2000 calories, added to my daily base requirement of 2000 calories that means to maintain my weight I’d need to consume 4000 calories. If I consume less I lose weight, consume more and I gain weight. I don’t look at when I’m losing weight but rather the overall picture.

Calorie expenditure in recovery specifically I imagine would be less quantifiable and given that you are more reliant on protein, with a lower calorific value, the figure would be smaller too.
Edit: Your metabolism will probably also increase if you gain lean muscle mass so you burn more calories at rest too.

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Thanks @Smurf I am 77kg, so not really looking at losing weight (although would like to be closer to 72kg ready for MTB season), just more of one of those questions that come in your head when you are day dreaming on the trainer

Is that actually true though? My understanding is that for an hour of all out race pace…you’ll essebtually burn the same amount of fat as you would during an easier endurance ride.

I was under the impression the only thing that changes significantly is the total amount of sugar burned (which obviously impacts the % each comprises of the total). I dont think fat calories burned actually decreases with intensity. I might be wrong…

This is the right answer.

Don’t bother with fat or carbs, worry about calories in and calories out. If you run a caloric deficit you’ll lose weight, if you don’t - no matter how much fat or carbs you burn, you won’t lose weight.

Depends on the type of calories consumed. 300 cal from quinoa has a very different metabolic effect than 300 cal from a doughnut.