Hunter, JR, Gordon, BA, Bird, SR, and Benson, AC. Exercise supervision is important for cardiometabolic health improvements: a 16-week randomized controlled trial. J Strength Cond Res 34(3): 866-877, 2020-Exercise supervision enhances health and fitness improvements in clinical populations compared with unsupervised or home-based exercise, but effects of supervision type are unknown in healthy employees. Eighty-five Australian university employees (62 females; mean ± SD 43.2 ± 9.8 years) were randomized to personal (1:1; SUP, n = 28), nonpersonal (typical gym-based; NPS, n = 28) supervision or unsupervised control (CON, n = 29) exercise groups. Subjects received a 16-week individually tailored, moderate-to-high intensity aerobic and resistance exercise program completed at an onsite exercise facility (SUP and NPS) or without access to a specific exercise facility (CON). Repeated-measures ANOVA analyzed changes to cardiometabolic outcomes. Mean ± SD increases to V[Combining Dot Above]O2 peak were greater (p < 0.01) with SUP (+10.4 ± 11.1%) vs. CON (+3.8 ± 8.9%) but not different to NPS (+8.6 ± 8.2%). Compared to CON (+1.7 ± 7.7%), upper-body strength increases were greater with SUP (+12.8 ± 8.4%; p < 0.001) and NPS (+8.4 ± 7.3%; p < 0.05). Lower-body strength increases were greater with SUP (+26.3 ± 12.7%) vs. NPS (+15.0 ± 14.6%; p < 0.05) and CON (+4.1 ± 12.4%; p < 0.001), and NPS vs. CON (p < 0.01). Body fat reductions were greater with SUP (-2.2 ± 2.2%) vs. NPS (-0.6 ± 1.9%; p < 0.05) and CON (-0.7 ± 1.9%; p < 0.05). Access to an onsite exercise facility with personal or nonpersonal exercise supervision was important for improving several cardiometabolic outcomes, with greater improvements to lower-body strength and body composition from personal 1:1 exercise supervision.