I think a lot depends on age and your individual metabolism. When I was younger, I lost weight easily with just about any moderate level of bike time. Now, bike time has almost no correlation with weight loss. Now, it is more driven by calorie intake moderation. If I can keep my calorie intake in the low 2,000s, I can lose around 2 lbs./week while exercising. If not, I stay the same no matter how much exercise time I put in.

I am currently doing around 10 hours/week on all three while also trying to drop some tonnage. Around 5 hours is intense bike time. Equivalent to around 100 miles/week if it was outside.

Two things:

Diet for weight loss, exercise is kinda irrelevant in that sense. Eat lots of whole foods, mostly plants, you'll be good. Also fuel on the bike, otherwise you'll just end up binging after.

What work you do on the bike, you're generally better off keeping it aerobic, don't go too hard. Lots of intensity+caloric restriction is a bad combination for the most part.

Basically, the answer to your question is as much volume as you have time to do while making sure you still get good sleep and take care of yourself. If you're stressing yourself out about things you need to do, not sleeping, or eating out because you don't have time to cook, you're also not going to lose weight. Probably not what you want to hear, but it's the only answer that is going to work.

I think it would be a lot less about the miles, and more about the kjs/kcals you're burning. 6 miles up the mountain is the same as 21 miles on the flat for me...

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"I'm thinking of a number between 1 and 10, and I don't know why!"

You're on the right track, more miles generally equates to more weight loss. But, you can't out bike a bad diet (duh). For reference, 10 hours per weak at 200 watts average works for me on a mediocre diet, meaning cheeseburgers are allowed, but not the fries.

per this picture, it is easy to gain weight riding a lot of miles. So fix your diet, go less aero...get a fixed gear bike.

My initial response was going to be infinite, as for me I've only lost weight when running, cycling I just change some fat for muscle on my calves and quads.

But then I thought harder and realised that I did manage to lose 20kg a few years back coming off being long term injured and initially it was almost all cycling. What I recognised that time was that presioly, cycling 400+km a week I was doing this with sports drinks in the bidon, and chomping gels during those rides. They had been lots of long rides, normally 3 x 80 km rides a week and a long ride on a Saturday or Sunday.

When I lost a lot of weight, initially it was restricted to zwift (post ankle operation, was in moonboot for walking but could cycle). But I was doing an early morning ride every day fasted. Initially modest effort but then doing the 1 hour duration races. And then added a second race on an evening a couple of times a week. Then doing the long group ride, but just with nuun and half a cliff bar after 2-2.5 hours and then the second half after 4 hours or so. When I got home, a good recovery shake instead of getting home and refuelling with full lunch. Couple of rides I bonked and the last 15km were slooooow, but I made sure I had 2 gels in my pocket as emergency supplies if I needed, but never did.

So back to your question. I'd say it's about choosing the right mix of intensity vs duration, being very mindful to not ingest 800cals of drink and bars and cake at end for an hour and a half ride. How much, well perhaps and unfortunately enough to make you feel hungry, hungry enough to eat that apple you have handy and not raid the choccy bar drawer, but not hungry to the point you are feeling weak.

Anecdotal experiences about how much cycling someone was doing when they lost weight is almost completely useless as it's completely dependent on how much they were consuming. For example I've lost weight while doing pretty much zero aerobic exercise and I've maintained weight while doing 20+ hours a week, the key difference was kcal consumed.

Simply put if kcal in < kcal out you will lose weight. Of course exercise bumps up the kcal out side of the equation so can certainly help. However as said above it's pretty hard to out train a bad diet - it's a lot easier (and quicker) to eat 2000kcal than it is to burn that much through exercise.

Optimum intensity for weight loss is an interesting question. At high intensity kcal/min is obviously a lot higher, but it's unsustainable for such long periods, especially without fueling. Low enough intensity with a decent base should be mostly fat oxidation, so spares glycogen meaning no bonking or refueling (at least theoretically!).

My personal point of view is you shouldn't try to diet on the bike. Better to fuel appropriately to maximise training and cut kcal elsewhere. However, you make a good point that people can over do it at times with fueling. For an easy zone 2 ride you don't need to be crushing gels and carb drinks. Also people tend to overestimate how many kcal they burn through exercise and then go overboard with eating later on that day (power meter comes in handy here for getting a more accurate estimate of kcal burned).

It's a bit of a fine line. Eat too much and you will gain/maintain weight. Eat too little and workouts suffer and you risk losing a greater percentage of muscle than you would with a small kcal deficit. That's why it's a lot better to try and get a decent estimate on your kcal in and out than just blindly diet/exercise.

This is obviously not the whole story. But for fun I have this saved -

Burn calories cycling:

1W = 1 J/s

10,000 kcal = 41,840,000 J

Since 80% of E produced is lost as heat, we need to produce 20% of that E as power on the bike to equal burning that amount in total.

= 2,324 hrs at 1W/hr

So 2,324 / “n” W per hr = hours needed to ride to burn 10,000 kcal.

35% of that (for 3,500 kcal = 1 lb ) is 813.4.

If I average 180 W/hr, I’d need to ride
814/180 = 4.5 hrs

So riding 4.5 hrs at ave 180 W effort will burn 1 lb

Not accounting for calories taken in to fuel the ride

Have you ever read Racing Weight by Matt Fitzgerald? That’s the compass point of endurance athlete diet. Highly recommended.

According to my Garmin, my last ride was 66 minutes and I covered 26.5 Km ( 16 1/2 miles) This is "in town" riding on bike paths and beside the lake. I'm almost 6'0 on a good day, currently weight 190 lbs. I burned 650 calories (according to the Garmin). There's about 4,100 calories in 1 lb of fat. I only drink water on these rides. The following is based on not eating after. If you do eat anything that will change the time frame. If you have open roads and no stops, you might use a few more calories.

On that basis without changing my normal diet, assuming I eat only a neutral diet (no gain, no loss) before exercise. I will lose 1 lb every 6.3 days of riding. or 1.11 lbs every 7 days of riding ( 115 miles a week) and that translates to 20lbs in 127 days of riding (divided/multiplied by however many rides/miles you do a week). You can ride faster or longer or hilly'er and alter those parameters. If you eat more (to recover) it will take longer. If you use gels during the rise, deduct the calories from the ride total.

When all is said and done, that's about what it takes.

I race at around 170/175 and it takes me 3 months to get there (from whatever spring month I start) most years. And there's usually a little running and swimming involved and 10 hours a week unless it's an IM year.
Good luck.

How much you ride is completely irrelevant. If your diet sucks you can't ride that away. If you burn 900 calories riding but go to five guys and get 2 burgers and fries then go home and have a few beers you will not lose weight/fat.
What does your diet look like? Do you track your foods?

I never found exercise to really matter much, other than a lot of aerobic exercise and particularly at a high intensity just made me very hungry. For me always came down to controlling calories in not calories out.

I have a fundamental question about power meters. Is the power read out from the power meter just the power put through the pedals, or is it the entire power being generated by the body including all the metabolic functions that don't directly push the pedals?

Returning to the original question, my Samsung phone tells me I expend about 35 calories per mile. The only data my phone has is my speed and distance from GPS plus my pulse rate from my watch and the weight that I recorded in the app (145 lbs), so I assume this is total metabolic power, not just the power pushing the pedals. If this is right, then I burn one pound (3500 calories) per 100 miles.

I rode 500 miles in a week and gained weight during RAGBRAI. Weight loss is almost all about food intake.

I find that I burn ~1000 cal / hour if I’m riding really hard, or ~600 for moderate effort. ~300 for easy rides. Figure I average ~20mph

your 35cal / mile calc is reasonable. However, it’s dependent on how hard you’re riding

The power meter is measuring force you are applying at the pedal. That's it.

You can't go by the 100 mile/pound unless you are riding the same miles on the same road in the same conditions. Even a slight head/tail wind could skew this greatly.

I burned 1,953 calories yesterday talking 9600 steps (According to the Garmin). I'm pretty sure that's not right. :)

Every so often my Garmin goes a little wonky or maybe I do.
Garmin also takes into account heart rates and sometimes that goes a little wonky.......
Running is always way more calories than cycling.
Was it a 10k uphill?...;0)

My comment was supposed to be a joke. It wasn't in an activity, that's just the additional calories it adds for activity onto my daily calories. It was almost all walking the dogs.

That is what I typically get, so I don't think it calculates active calories properly for me. I'm sure it's more accurate when recording an actual activity, at least when I run or bike it seems more inline with reality.

Big dogs......? :0)

I have lost weight riding 0 miles per week.

I have gained weight riding 300 miles per week on a MTB.

Weight loss happens off the bike, and almost completely regardless of the bike.

For you, your weight loss happy number probably falls between 40 miles per week and 200 miles per week. :)

How do I know?

Some activity is good. Hence 40 minimum. (half what you're currently doing)

Training overload can cause substantial fatigue, which if not combatted with increased sleep duration, leads to increased eating, in most humans. Hence 200 max. (2.5 times what you're currently doing)

FYI: These numbers are all pulled out of thin air just to illustrate my point.

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Dr. Alex Harrison | Founder & CEO | Sport Physiology & Performance PhD
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Well, I wouldn't call them big, but they're not short. (The one on the ground is around 31 inches at the shoulder.)

No wonder......those are not dogs that just walk.
Gorgeous animals, I understand they are slightly daft.

As someone who is active, but has struggled with weight, I am qualified to say: Weight loss is all about eating fewer calories.

Depends on what you mean by daft. They aren't dumb, but they aren't very obedient. They are playful, silly, stubborn, independent, and sometimes crazy. When they misbehave, they know they are doing stuff they aren't allowed to, they just don't care.


Dog intelligence often gets mixed up with obedience, something that 'The Intelligence of Dogs' freely admits. Borzoi certainly ranked pretty low on Stanley Coren's list. But, as puppies our dogs learned to sit, shake, and lie down in about 5 minutes. Roll over took a bit longer, but these days they check treat value first. The higher the value, the faster they do what you want.

Here you can see them in action. It's the video the picture I posted is from.

can see all of that, in the picture you posted.. great pic ;-)

Alan Couzens posted on twitter recently, https://twitter.com/.../1518944744310657030




my brother got rid of about 30lbs by bike commuting instead of driving to work. He's known as 'Flatbar' on the group rides, showed up to his first group ride on his commuter with flat bars..

Swim. :) My N=1 experience was that when I swam a lot, I couldn't keep the weight on. But that was in my 30s. Doubt that would magically happen anymore.

You burn 1 cal per 1kg body weight per 1km run. That amount is 1/4th on bike. .25 cal per 1kg per 1k

Keep it simple:

1. Watch your food intake. If your eating bigger based on the fact that you worked out, you're probably cancelling any calories you burned.

2. Adding some basic strength training 30-45 mins 2x per week will be worth more than putting in more miles in the same amount of time. Do all muscle groups to boost overall muscular metabolism. Unless you're hitting it real hard doing tons of reps 4x/week and packing lots of protein and carbs post workout, you'll see little if any weight gain from the lifting.

Good luck!

Best

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Matt Leu, M.S. Kinesiology
San Pedro Fit Works, Los Angeles, CA
Endurance Athlete and Coach
Consistency/time=results

278 average watts in an hour = 1,000 kJ.

Definitely a solid workout for most.

Go to bed hungry. It is a strategy that works for me and has a great feedback mechanism without doing any calorie counting. Going to bed and not hungry? Less eating/more exercise tomorrow. It does not take long to dial in. Of course, your diet should not be all junk...

Find a nice long climb and do it repeatedly. There are no fat climbers because they either lose weight or quit.

Do more fork downs and ride your bike as much as you want.

That doesn't work. I've tried it. I got marginally better at climbing and got to where I actually looked forward to it, but I didn't lose weight by climbing 3-4 times a week.

Calorie deficit

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Andrew Garwood
http://www.2xu.com
http://www.newtonrunning.com
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