Study: Only HIIT Preserved Muscle in Older Adults — SkimNews
Get the Health newsletter
Daily health & science — research, biotech, public health, the studies worth knowing. Free.
- University of the Sunshine Coast researchers tracked 123 healthy adults (average age 72) through three supervised 45-minute gym sessions per week for six months and found only the HIIT group preserved lean muscle while shedding fat, with moderate-intensity training producing a small decline in lean tissue.
- Lead author Dr. Grace Rose said high, medium, and low intensity exercise all led to modest fat loss, but 'only HIIT retained lean muscle,' while both high- and moderate-intensity groups also saw improvements in visceral abdominal fat.
- Co-author Dr. Mia Schaumberg explained the likely mechanism: HIIT's repeated short bursts of very hard effort place greater stress on muscles, 'giving the body a stronger signal to keep muscle tissue rather than lose it.'
- The researchers cautioned that the scans measured lean tissue rather than muscle strength directly—lean mass includes water and other tissues—and that the differences versus lower-intensity exercise were 'not clearly clinically meaningful' after accounting for measurement uncertainty.
- A separate 2026 study in Medicine & Science in Sports & Exercise found 20 adults aged 61–74 lost an average of about 1.4 kg of fat after eight weeks of remotely supervised at-home HIIT, with 96% workout adherence and no adverse events reported.
- A Journal of Clinical Medicine review of 25 reports covering roughly 2,818 participants found HIIT's most consistent benefits were cardiovascular fitness gains, and did not establish that HIIT was consistently superior to moderate-intensity exercise across outcomes.
Why it matters: For adults over 70 aiming to stay independent—climbing stairs, rising from chairs, keeping their balance—preserving lean tissue matters as much as losing fat, and HIIT appears to offer that dual benefit in a structured gym setting. But the lead authors themselves flagged the muscle-preservation edge as not clearly clinically meaningful against moderate exercise, so the headline shouldn't push older adults away from the moderate workouts they can actually sustain.
Ask SkimNews
