Can high-intensity training reverse biological aging in older adults? Our research says yes.
"Maximal oxygen uptake (VO₂ max) is perhaps the most important physiological indicator of physical health today," says Jan Helgerud, Professor of Medicine at NTNU.
While the benefits of high-intensity training for younger people are well-documented — helping prevent lifestyle diseases and reduce early mortality — relatively few studies have explored its impact on older adults. Most research has focused on moderate-intensity training in older adults. But Helgerud, along with colleagues Jan Hoff and Håvard Østerås, wanted to test something different:
Can interval training offer the same — or better — benefits for people over 65?
Helgerud and team conducted a 10-week study on 21 healthy but previously inactive individuals aged 69 and older.
Previous research suggests this type of training can improve oxygen uptake to a degree equivalent to turning back the biological clock by ten years — in just ten weeks. The increase in oxygen uptake is primarily due to the heart’s enhanced pumping ability, especially a greater stroke volume — meaning more blood is pumped with each beat. This results from both higher cardiac output and stronger heart contractions. The biggest gains in oxygen uptake come from high-intensity intervals — specifically, four sets of four minutes each.
After ten weeks, participants improved their oxygen uptake by 4 ml/kg/min, a gain equivalent to turning back their biological clock by 10 years. Even a modest improvement in physiological function can enhance physical performance and promote greater independence in older adults.
This science-backed training method consists of:
The term high-intensity may sound intimidating, but it doesn't mean pushing yourself to the point of exhaustion. The 4x4 interval method is about staying at a challenging, but manageable, pace — whether you’re walking, jogging, or running. You should feel like you could go one more minute at the end of each interval. If you can carry on a conversation, the intensity is too low.
Tip: Use the Myworkout GO app for your next 4x4 interval session. Based on the research of Professors Helgerud and Hoff, the app provides guided workout instructions and scientifically accurate VO₂ max measurements — so you can train smarter and track real progress.
🕒 Time required: Just 32 HIT minutes per week.
“Fitness is perishable. Three weeks of bed rest can age you by 30 years.”
— Dallas Bed Rest and Training Study (2001)
Helgerud notes that although work capacity naturally declines with age, inactivity often causes an even steeper drop. That’s why staying active is critical to preventing lifestyle-related illnesses as we grow older. Many older adults believe slow, long walks are enough. But research shows that intensity, not just duration, is key to reversing the effects of aging and inactivity.
Helgerud emphasizes that it’s never too late to build strength, boost endurance, and reclaim energy — no matter your age.
Add a hike or walk on weekends, and you could maintain the biological health of a 20-year-old well into your 80s.
📖 Read the Study:
Effects of High-Intensity Endurance Training on Maximal Oxygen Consumption in Healthy Elderly People
Get in touch
Resources
