Previous studies measuring or estimating the energy expenditure of stair climbing.

*<p>Calculated from values.</p>**<p>Estimated from Figure 2 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0051213#pone.0051213-Butts1" target="_blank">[23]</a>; values at 95 steps per min.</p>†<p>Statistically significant difference.</p>§<p>Where single and double step conditions were undertaken, the value given is the mean across conditions.