Figure 4.

Adjusted means of gait speed, SPPB score, chair stand speed, leg peak power, and VO₂peak across performance fatigability severity based on identified PPFI cut-points in the Study of Muscle, Mobility and Aging (SOMMA; N = 805). Adjusted means were calculated using generalized linear regressions after adjusting for study site, age, sex, race, height, weight (except for the models with leg peak power and VO₂peak), and smoking status. Obtained from usual-paced 400 m walk. There were n = 1 participant missing SPPB score and chair stand speed, n = 34 participants missing leg peak power, n = 51 missing VO₂peak. PPFI = Pittsburgh Performance Fatigability Index; SPPB = Short Physical Performance Battery.