Cold water?

[Gidds]

Ok since water sucks away body heat at a much higher rate than air one burns a lot of calories when in the water right? Does this mean that that swimming or other forms of submerged exercise burn more calories with less strain than say biking or jogging? When referring to calories (or energy or whatever) here are we talking about those from whatever it is that you've recently consumed or could one actually reach a level of metabolism where fat is being utilized? (Sorry dunno much about exercise pysiology)

So what if I spent an hour bobbing around in the water, but not necessarily swimming laps, would that use more or less energy than if I went and rode my bike for an hour?

 

[ScubaSixString]

Ok since water sucks away body heat at a much higher rate than air one burns a lot of calories when in the water right? Does this mean that that swimming or other forms of submerged exercise burn more calories with less strain than say biking or jogging? When referring to calories (or energy or whatever) here are we talking about those from whatever it is that you've recently consumed or could one actually reach a level of metabolism where fat is being utilized? (Sorry dunno much about exercise pysiology)

So what if I spent an hour bobbing around in the water, but not necessarily swimming laps, would that use more or less energy than if I went and rode my bike for an hour?

Actually they did a study a few years back. They found that regualar swimming in cold water actually made you retain fat (as an insulative layer). Might be a bit counter productive.

 

[CameronMartz]

Ok since water sucks away body heat at a much higher rate than air one burns a lot of calories when in the water right? Does this mean that that swimming or other forms of submerged exercise burn more calories with less strain than say biking or jogging? When referring to calories (or energy or whatever) here are we talking about those from whatever it is that you've recently consumed or could one actually reach a level of metabolism where fat is being utilized? (Sorry dunno much about exercise pysiology)

So what if I spent an hour bobbing around in the water, but not necessarily swimming laps, would that use more or less energy than if I went and rode my bike for an hour?

Sorry, but there's no free lunch in fitness. <g> Calories require work to burn, and no, you can't just sit in ice water and burn the same amount of calories as riding a bike. Regardless of how the calories are burned (thermogeneration or exercise), you still need to support it with a rise in respiration and heart rate. If you do not have a comparable rise in resipiration and heart rate for a substitute activity, you are not burning the same amount of calories.

Additionally, calorie burning is only one goal of exercise. This alone does not create fitness- it just reduces body fat. You need sustained, elevated heart rate for cardiovascular conditioning to increase endurance, decrease SAC, and increase your resistance to DCS. You also need muscular overload to increase muscle, bone, and joint strength and health.

Cameron

 

[Gidds]

I wasn't suggesting hypothermic experiences as a fitness routine I was just curious about how the energy was used.

 

[TSandM]

The first adaptation to cold surroundings is peripheral vasoconstriction, lowering the blood supply to the skin and extremities to reduce heat loss. You really don't kick up your calorie consumption until you begin to shiver, and at that point, your energy use skyrockets. However, shivering is a sign of falling core temperature and isn't a very safe condition to remain in for very long. So the answer is no, remaining in cold water or cold surroundings won't burn significantly more calories until you get too cold to stay there any longer.

 

[Gidds]

Ok all that said what is an ideal temperature for exercising? (sorry if that sounds random, my thought process is strange) I despise exercising when it's hot (read humid) but I don't especially like the cold either. Why do I feel more hungry after diving or snorkelling than after swimming laps? I definately respire at a higher rate while swimming laps but I usually do it for less time than diving or snorkelling and I swim in warm water as opposed to snorkelling or diving in the ocean or lakes. However, when I dive or snorkel it's not like I'm breathing fast and heavy like when swimming and I usually wear a wetsuit when even just snorkelling.
Oh also if vasoconstriction of the extremities is what happens when you get cold, and I suspect that I have crappy circulation to begin with, is that why I have never been able to hold my heat in the water or otherwise even after gaining some weight? Are any of these principles related to why I feel cold after eating? I always thought it was because my blood was being shunted to my stomach and intestines butlike I said before human physiology isn't my thing.

 

[scuba-punk]

Your ideal temperature for exercising is the one that you can tolerate. If you don't tolerate lots of heat well, then try working out in the morning. Where I live, the evenings in the summer are still hot and humid even after the sun sets. It does take some time to acclimate if you are just getting started. Nothing says that you have to start working out at high noon in the middle of summer and go all out. That would be counter productive. Like Cameron mentioned, the key is to get your heart rate up (in the appropriate range). Do something that you enjoy and can do consistently. That's the key.

Sorry, but I can't help much with regard to the hunger stuff. After a one hour dive, I'm a little hungry, but I also don't eat much before going for a dive. After a 4 hour bike ride however, I'm ready to eat anything in sight

The vasoconstriction stuff will happen to varying degrees. It's a self defense mechanism. It's important for your body to not let your blood cool down a lot. Think of your hands, feet and head like a radiator in a car. Keep those extremities covered to limit the amount of heat you lose.

-Frank

 

[Hank49]

I wasn't suggesting hypothermic experiences as a fitness routine I was just curious about how the energy was used.

I find that if I snorkel for extended periods ( when scuba diving I try to stay warmer) that I urinate quite frequently. And I've weighed myself before and after a 4-5 hour spearfishing session. I lose up to 5 lbs in a day (183 down to 178 or so). But I believe this is due to the immediate bodily response to the cold, which is dump off any excess liquid that requires a lot of energy to keep warm. This happens before the shiver stage of getting cold. But then at night after I eat and shower, I'll drink about a half gallon of water and by the next day, my weight is back up.

 

[TSandM]

The physiology behind increased urine output underwater is not related to temperature. It is related to hydrostatics. When you are on land, gravity is always pulling your blood to the lowest part of your body. The hydrostatic forces in the legs when standing, for example, favor liquid transudating OUT of the blood vessels and into the tissues (which is why ankles tend to swell in people who work on their feet). When you lie down at night, this fluid moves back into the circulation and is "counted" as part of your blood volume again, and your urine output goes up.

Underwater, you are subject to far less effect of gravity, and in addition, you have compressive forces from the surrounding water. These tend to favor fluid staying in the blood vessels, which makes your effective blood volume greater and encourages urine output. This is independent of the temperature of the water in which you are immersed.

Peripheral vasoconstriction begins at the capillary level. This will occur even in people who have truly poor circulation (i.e. significant arteriosclerosis).

Inability to maintain core temperature well in cold surroundings can be related to low basal metabolic rate (eg. poor fitness, low thyroid, low muscle mass) or poor insulation (low body fat) or inadequate protection. In addition, people vary in their subjective sensitivity to cold. Some factors are predictable, and some are simply individual.

 

[Hank49]

The physiology behind increased urine output underwater is not related to temperature. It is related to hydrostatics. Underwater, you are subject to far less effect of gravity, and in addition, you have compressive forces from the surrounding water. These tend to favor fluid staying in the blood vessels, which makes your effective blood volume greater and encourages urine output. This is independent of the temperature of the water in which you are immersed.

.

Ahh, this makes sense. I think. The hydrostatic pressure would have more effect on a scuba diver at 2-4 bar pressure than it would a free diver on the surface. Is this why I seem to have to pee more right after surfacing from a 60-70 foot free dive?
And to think all these years.. :idea3: ...Because I also used to see this effect when I was haresting prawn ponds at about 18-22 degrees C. I was only in the water up to my waist but I would urinate about a gallon in a few hours. :ice: I always thought it was the cold.