We report the effects of treadmill exercise on (18)F-FDG uptake in skeletal muscles and image quality of torso PET and compare stress myocardial perfusion imaging patterns with myocardial (18)F-FDG uptake. There were 3 groups of patients: 48 patients underwent PET within 8 h after a treadmill test (Ex 8), 45 patients within 48 h after a treadmill test (Ex 48), and 34 patients without prior exercise. Mean workload (8.4 ± 2.3 [Ex 8] vs. 8.9 ± 2.6 metabolic equivalents [Ex 48]) was similar in both exercise groups. Muscle uptake was assessed by standardized uptake value. Myocardial uptake patterns were compared visually. Minor differences between patient groups were noted only for maximum standardized uptake value in quadriceps muscles. There was no correlation between perfusion defects and myocardial (18)F-FDG uptake patterns. Thus, treadmill exercise does not affect muscle (18)F-FDG uptake or image quality on subsequent PET. Cardiac (18)F-FDG uptake on torso PET scans is unrelated to myocardial perfusion status.