Figure 3. Bioenergetic Health Index (BHI) calculation and correlation with lifespan extension. BHI either (a) plotted against % increase in mean lifespan for all tested RNAi; or (b) calculated for mild (parental generation) and (c) strong (first generation) RNAi-mediated suppression of nuo-5, lpd-5 and spg-7. % decrease of BHI compared to control is shown on the corresponding bar.