I live in arizona im trying to cut down on bodyfat by sprinting…Now its Arizona so its 120 degrees does the extra heat help burn more calories enabling me to have shorter sessions or should I still do the same amount of running as if I were indoors…
I am pretty sure that it is the opposite. When it is colder, your body burns calories to maintain heat. For sure though, you’ll lose weight in the heat, but it is all water. And I don’t believe calorie expediture is enough to make a big difference.
I think you would be best training in the AM or eveining when it is cooler. You can train harder, without worrying about overheating. Don’t forget to stay hydrated.
Paranoid Strength,
Actually you will burn more calories in the heat. This is due to the increased cardiorespiratory and thermoregulatory demand placed on your body while exercising in hot weather.
Exercising produces heat which must be dissipated to avoid developing heat related injury/illness (heat exhaustion/heat stroke etc). The body has four different mechanisms by which to rid itself of excess heat: radiation, conduction, convection and evaporation.
In very hot weather, the body actually will gain heat from the environment in addition to the increased heat from the exercising muscles. Evaporation (sweating) is the main way the body loses heat while exercising in a hot environment. Also, the sweat must evaporate from the skin surface to have any real cooling effect. Therefore, humidity is a major factor. In Arizona, where the air is dry, you will evaporate more efficiently and therefore cool more effectively than if you are in both a hot and humid environment where sweating is more inefficient.
Evaporation of 1 liter of sweat is equivalent to about 580 kcals.
Also, if you try to run the same pace outside in the extreme heat that you normally run indoors, your perceived exertion will be higher because your heart rate has to be increased to maintain cardiac output as your stroke volume will decrease. Sometimes it can be as high as 10 beats per minute faster at the same intensity level. Obviously this could result to earlier fatigue or decreased performance.
The main thing is to be safe, not to worry about calories. Try not to exercise in the heat of the day, exercise in the shade if possible. Wear light colored, light weight moisture wicking fabrics and expose as much surface area as possible (without getting arrested). Obviously maintaining fluid balance is crucial.
If you have any follow-up questions, please let me know.
Take care,
Ryan
Dr. Ryan,
By no means do I mean to argue, but I could swear I learned that you burn more calories in the cold. Do you burn more calories resting in the cold than in the heat, or am I just way off base?
[quote]combatmedic wrote:
Dr. Ryan,
By no means do I mean to argue, but I could swear I learned that you burn more calories in the cold. Do you burn more calories resting in the cold than in the heat, or am I just way off base?[/quote]
at the south pole, without any external heat source, your body needs 7,000 calories a day to produce enough heat to survive.
humans can take some serious cold, but we die in very high heat.
so being cold does burn calories, just as being hot does. the thing of it is that we can get a lot colder that we can be heated up.
i think that the heat may burn a few more kcal but this is not major. Focus on diet and training and you will be better off than cranking the thermostat or training in hot weather.
also, if you overheat, and spend time in the hospital you tend to burn less calories. Seriously, take your health into consideration. If the temp is 120 and you are working out in that heat, do you think that it is safe?
best wishes be safe