Uphill walking may outperform running when it comes to fat burn and long-term physical resilience, according to a recent post on X by biohacker and Upgrade Labs founder Dave Asprey.

Citing a new study comparing treadmill incline walking to traditional running, Asprey argued that walking uphill taps into fat stores more efficiently—without spiking stress hormones or breaking down muscle.

“It’s about time you quit breaking down your muscle with running, and work smart not harder,” Asprey said in a follow-up. “Just following the science.”

He pointed to REHIT (Reduced Exertion High-Intensity Training) as an even more effective method for fat loss, especially when paired with AI-assisted exercise bikes offered at his Upgrade Labs facilities.

The study he referenced, published in Evidence-Based Complementary and Alternative Medicine, analyzed participants completing a 12-3-30 treadmill walking protocol—12% incline at 3 mph for 30 minutes—compared to self-paced running. Researchers found no significant difference in overall energy expenditure between the two workouts. However, the incline walking session showed greater fat oxidation and lower respiratory exchange ratios, indicating the body relied more heavily on fat as a fuel source.

Completion time and exertion levels also differed, with incline walking requiring more time but less intense muscular strain. The authors concluded that incline walking may offer unique metabolic advantages for individuals seeking fat loss without the musculoskeletal impact of running.

The full study is available here.

Asprey is a long-time advocate of biohacking and alternative wellness methods. He founded Upgrade Labs to explore science-based approaches to optimizing energy, strength, and overall health.