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Heat limited running paceIn hot conditions, your maximum running pace is limited by your ability to cool off. It is possible to calculate your theoretical maximum running pace at a particular temperature and humidity given your height and weight. This calculator is based on my [[Running Heat Model]].
The In addition to the caveats in [[Running Heat Model]], the calculations of maximum pace make lots of extra assumptions. '''This means that the pace indicated may not be safe'''. * Your running efficiency may be different to the average. A higher efficiency will produce less heat at a given pace, a lower efficiency will produce more heat. =See Also=* The only air movement is assumed to be from running through still air. Running calculators** Any wind can make a significant difference, with a headwind or crosswind cooling your off. A tailwind less than twice your running pace will reduce your cooling; it takes a tailwind of at least twice your running pace to cool you off more than still air, but of course a tailwind will reduce the energy required to run. [[Running Heat Model]]* The calculations assume negligible clothing. If you are wearing more than the absolute minimum clothing, this will impair your ability to cool off. * [[Perceived Temperature For Runners]]* It is possible to actively cool off with ice, which will allow you to tolerate higher temperatures. * Any direct sun will increase the heat stress and dark clothing will make this worse. =Heat Acclimation Training=''Main article: [[http://fellrnr.com/wiki/Heat_Acclimation_TrainingOptimum Running Temperature]]'' Heat Acclimation can improve your ability to keep cool by sweating more and sweating earlier, as well as making your sweat more dilute. Heat adaptation can also teach you the warning signs of an elevated core temperature so you can adjust your pace or take action to cool off before things get dangerous. However, heat adaptation does not change the limits of physics, nor does it allow you to tolerate a higher core temperature. =Advanced notes on calculations=These notes are for those with an interest * [[Running in the underlying details.Heat]]* There are multiple formulas for calculating water vapor pressure which produce slightly different results. [[Heat Acclimation Training]]* The calculation [[Impact of skin temperature is not straightforward. The calculator uses Neilson's simplistic approach for 0 Celsius to 15 Celsius, then Mehnert for above 15 Celsius. * The maximum running pace is calculated using a goal seek algorithm. * The various formulas for calculating the surface area of the skin appear to give similar results.Heat on Marathon Performance]]
→See Also
=Introduction=
When you run, you produce heat that must be removed from your body. In cold conditions, this is not a problem, but as the temperature and humidity go up, it becomes harder to remove the generated heat. If you generate more heat than you lose, your core temperature will rise and you will have to slow down. For most people, the rise in core temperature causes a gradual, though unpleasant, slow down. However, extreme dedication can force some people to push hard enough to raise their core temperature enough to cause collapse, coma and even death.
=Basic Heat Calculationlimited pace table=The basic heat calculation is from <include_PHP file="HeatMaxRunningPace" />=Input Form=<html> <form style="font-family: Helvetica,Arial,sans-serif;" method="get" action="/wiki/Heat_limited_running_pace" name="HeatLimits"> <table style="text-align: left;" border="1" cellpadding="1" cellspacing="1"> <tbody> <tr> <td>Height</td> <td> <table style="text-align: left;" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td><input maxlength="3" size="3" name="Height" value="70"></td> <td> <select name="HeightUnits"> <option selected="selected">Inches</option> <option>Centimeters</option> </select> </td> </tr> </tbody> </table> </td> </tr> <tr> <td>Weight</td> <td> <table style="text-align: left;" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td><input maxlength="3" size="3" name="Weight" value="135"></td> <td> <select name="WeightUnits"> <option>Kg</option> <option selected="selected">Pounds</option> </select> </td> </tr> </tbody> </table> </td> </tr> <tr> <td>Temperature Units</td> <td> <table style="text-align: left;" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <select name="TempUnits"> <option>Centigrade</option> <option selected="selected">Fahrenheit</option> </select> </td> </tr> </tbody> </table> </td> </tr> <tr> <td>Temperature Increment</td> <td> <table style="text-align: left;" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <select name="TempInc"> <option>Fine</option> <option selected="selected">Course</option> </select> </td> </tr> </tbody> </table> </td> </tr> </tbody> </table> <input type="submit" name="mysubmit" value="Generate" /> </form></html> =Heat Acclimation Training=# ''Main article: [[Heat produced from running. This is dependent mainly on your weight. Acclimation Training]]'' # Heat lost (or gained) from convection. This is mostly dependent on Acclimation can improve your surface area (calculated from weight ability to keep cool by sweating more and height)sweating earlier, and as well as making your sweat more dilute. Heat adaptation can also teach you the air warning signs of an elevated core temperature. # Heat lost (so you can adjust your pace or gained) from radiationtake action to cool off before things get dangerous. This is mostly dependent on your surface area and However, heat adaptation does not change the air temperature.# Heat lost from evaporation limits of sweat. This is mostly dependent on your surface areaphysics, the air nor does it allow you to tolerate a higher core temperature and humidity.
=Important caveats=