Kalwall has good thermal insulation properties and allows a high level of daylight penetration, so its northerly aspect meant that there was little or no risk of solar heat gain throughout the year.

To get the most out of acclimatization, your indoor runs should be as close as possible to your race because you do lose the benefits you gain if you don't maintain the heat exposure.

This 12% requirement can be met by a combination of solar gain from a high number of south facing windows and the heat generated by people's cooking and hot water use.