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Calorie Questions from a personal trainer.

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Aug 9, 2002
This friend of mine is a personal trainer. I was talking to him about slower heart rates, and oxygen consumption. The subject eventually got around to calories burned during freediving. I quoted "Freediving" by Terry Maas, where he claimed that studies show that freedivers can burn 1,200 calories an hour! I am dieting and I am wondering how freediving and a slower metabolism underwater will affect my weight loss and he is wondering why we burn so many calories?

Any help would be...helpful
Only a guess till Eric or Frank or someone else will get to this thread:
My guess is that since a certain portion of our metabolism while freediving is unaurobic and there for, craetes lactic acid, the body takes energy to dispose this lactic acid, probably mostly in the liver, even if the liver doesn't need this extra energy that comes from breaking down the lactic acid, it'll still need to break it to lower levels of lactic in the blood.
Just one of my guesses, probably way off.

1200 calories... that's about what I ate yesterday... (I managed to count calories for the fist time in my life yesterday.)
I think that this amount is too high. I've been freediving for 4 hours consecutive atleast once, that means 4800 calories... you can feed a couple of families or a bodybuilder with 4800 calories.
I think the 1200 calories example is fairly high unless you're naked in 12C water. Which brings me to the main reason for the calorie consumption: ambient temperature in a medium that absorbs heat 24 times faster than air.
Ever notice how hungry you are after an hour in the pool? It's a result of your body burning huge quantities of calories to keep your core at operating temperature. Even sitting around in a 28 or 30C pool will burn calories, but the colder the water, the more calories burned. The better you are insulated the less calories burned.
If our friend Sven decides to try and prove his manhood by freediving SoCal coast this time of year, he will burn mega-calories (and suffer from severe shrinkage), but if he puts on his 5mm Picasso plus a 3mm vest, he will burn less (thereby retaining his manhood ;) ) .
So dive naked if you're fat :(
Cheers amigos,
Erik Y.

After years of diving in warm & cold water, I would say that it is mainly the water temperature that affects your calorie burning rate.

By monitoring my appetite after diving, and comparing it to my appetite after working out in the gym on cardio (with those computerized gizmos that tell you how many calories you are burning), then I would estimate for me:

Fun diving in warm water: 500 cal/hr
Fun diving in cold water (<12C): 1000 cal/hr
Hard diving (i.e. repetitive dives or surface swimming) in cold water: 1200 cal/hr (once you start shivering, 1500+ cal/hr)

So I think Terry Maas' estimate is accurate in rare cases.

The most calories I ever burned was on a hard training weekend; two consecutive days doing 20-30 dives per day to 30-55m with a 5mm suit, 15lb belt (penalty ballast), long surface swim, in 8C water, with short intervals between dives.

Each time we went to Red Robin afterwards, and I ate so much that my part of the bill was like $50 !

With the heavy weight belt penalty (and without lung packing), I was neutral at about 4-5m, and sinking like a bomb near the bottom. The point was to fail my legs on the ascent. On one of the dives to 53m, I counted 48 monofin strokes to get back up -- more than it took me on 80m+ dives with a thin suit and normal ballast!

Eric Fattah
BC, Canada

In a review article of Guido Ferreti (Eur J Appl Physiol 2001;84:254) He describes that in breath-hold divers the Vo2 max is lower than rest Vo2. So, theoretically the energy expenditure will be less than rest.
In dynamic breath-holds (I mean in movement) a great part of the energy comes from anaerobic metabolism. In anaerobic glycolisis you gain 2 ATP molecules for 1 of glycogen and with aerobic metabolism you gain 37 ATP molecules from glycogen (36 for Glucose), so you have to use more substrates to have energy.
As Erik said the thermogenesis is also a big part of it, to keep normal the core temperature "burning" of sustrates is necessary.
Thanks for the response!

So being in cold water, and swimming around a bit helps me burn more calories. This will positively affect my diet. good news, good news indeed. I really didn't think that it would be bad, but it was an interesting question. Decreasing heartrate/metabolism and trying to lose weight at the same time.


hi Karl

I take it your Frank's brother the guy who can hold his breath for 8mins. Pleased to have you here. Wow we now have two extreme apneists here Eric and Karl.

Welcome Karl, Franks speaks very highly of you :)

Tim, swimming is probably the best calorie burner for working out (comfort-wise), but one of the problems associated with using this method is that you come out of the water STARVING! So watch your food intake for a few hours after swimming :)
A lot of people don't realisw what a great workout swimming is, and the public perception is clouded by the fact that you see a lot of overweight people swimming laps. Swimming for overweight people is a lot easier than running or biking or lifting, but that doesn;t stop them from eating abnormal amounts when they're not swimming.
Ivan, there are quite a few extreme apneists online here, including DSV, David Lee, etc, etc. I would say that anyone doing 6+ minutes or 60 metres+ CB is extreme....:)
Erik Y.
I would say that anyone doing 6+ minutes or 60 metres+ CB is extreme....

Thanks Erik, I needed that.

Originally posted by TMcKee
"Freediving" by Terry Maas, where he claimed that studies show that freedivers can burn 1,200 calories an hour!

Hi T,

Any activity that implies the use of stored glycogen, especially the anaerobic type (which is freediving), needs a consequent replenishment if optimum performance is sought, unless the trainer is involved in a fat loss program, which is not our case (relatively speaking).

That glycogen replenishment should be done within the first 48 h after exercise, otherwise overtraining may result.

The body's preferred source of lost energy are carbohydrates, which contain 4 kilojoules (formerly known as calories) per gram. Protein also contain 4 kilojoules, while fat contain 9 kilojoules per gram. For instance, have you noticed how full you get if you eat raw avocado?

Why carbohydrates?

Have you ever heard about the Krebs cycle? There relies the answer, but I can't explain that here because I'd need forever to write the whole day to write it through this source.

O.K. , and about the other reasons some of the other guys have given you the answer: thermoregulation, or extra blood supply to the skin in order to maintain core temperature, which implies extra kilojoules. This will not apply to freedivers who exercise in a warmer fluid, i.e. tropical waters or a heated swimming pool.

Regards, gerard.
Originally posted by DeepThought

Now you're just bragging Erik. :D
But you're right.

...haha...ok, I admit it Michael! But we may have to change the parameters now that Karl has joined the 3 other guys in the world who are capable of 8 minutes+!!
Bill, you are extreme.....also extremely witty, jovial, and inspirational :)
Erik Y.
I eat 3000-4000 calories a day and I'm losing weight. Sometimes 5000. I freedive for about an hour or two in a cold pool 2-3 times a week, lift weights 2 times a week and walk everywhere. I'm 66kg.

I have trouble eating enough. It's one of those problems you can't complain about to anyone because they instantly hate you!

I'm guessing the calories are being used to warm me up when I'm in the pool.

I feel warmer and my heart rate is faster for about 6-12 hours after I dive - I'm guessing this is the muscles recovering from the oxygen debt?

I'd like to eat less because it's costing me a lot of money. I'm going to start wearing a wetsuit to see if that helps. Does anyone know why I eat so much? I'm on the paleo diet (high fat, low carb) and I eat some carbs after workouts.
I quoted "Freediving" by Terry Maas, where he claimed that studies show that freedivers can burn 1,200 calories an hour''.

When my friend Terry wrote that book ''Freediving'' may have had a slightly diffrent meaning?

Here in Cali in the blue water some of us are swimming against strong current while on ''freedive'' spearfishing drops averaging 2 mins all day from sun up to sun down. The water can be 54 degrees and I hate suits thicker than a well depth crushed 5mil so maintaining core temp can chew up a lot of Ensure and pasta. :)
Sorry I don't have any science to go with that, but I have never come home weighing more, even with ample hydration I have lost 7 to 8 lbs on a very physical weekend.

Cheers, Don Paul
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Does anyone know why I eat so much? I'm on the paleo diet (high fat, low carb) and I eat some carbs after workouts.

Paleo is good for weight loss (it is a variant of atkins after all) and a moderate to low exercise level, but for an anthlete... carbs are badly needed to re-energise muscles with glycogen.

You can follow a paleo diet (my diet is quite similiar, but I do eat carbs from fresh fruit and veg) I would tend to load up on carbs a few hours before activity and shortly afterwards. Then you can revert to your diet (I'm resisting the urge to call it a fad :) )

Afterall, paleolithic man didn't freedive... you body has different nutritional and dietary needs and if you dive deep I would be concerned about such a diet.

Your BMR should be about 1500 per day (what’s your height and age?) and your calorie expenditure should be about 2400 based on your suggested levels.

Basically, I am not sure you are eating as much as you think?

Whats your diet like?
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Well I think it's not all about having the right amount of calories, but also about how the body can handle it.

After listening to the following podcast I'm getting interested in experimenting with a weat-free paleolithic diet. I think I'll supplement it with whole grain rice for extra carbon.

Dr. William Davis interview – “Meat Wheat is Murder” – #131 - Gnostic Media - Gnostic Media

Also if you want to gain or loose weight the timing of your food is important. Always give the body what it needs soon after exercise. Easy to remember is to have food after the hunt (sport).
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