Key takeaways
Blood flow restriction (BFR) training uses specialized cuffs to partially restrict blood flow out of working muscles during exercise.
Using BFR with light-intensity weight training may be an effective alternative to high-intensity training with heavy weights.
It may be especially helpful for adults recovering from injury, with joint pain, and women in midlife.
Training with heavy loads is one of the fastest, most effective ways to build muscle and maximal strength, but it’s not always practical or comfortable. Maybe you're recovering from an injury, your knees ache during squats, or menopause changed how quickly your body recovers.
"If someone can lift heavy and they're not hurting their joints, and they don't feel incredibly sore, and they feel like they can recover, and they're still getting results, more power to them,” says Ashley Selman, MA, CSCS, a leading fitness trainer and the founder of Seli Strength.
For everyone else, lighter weights can build strong muscle, though it often takes longer and is not as efficient for reaching your muscles’ full potential. However, could there be a way to make light weights work more like heavy ones? With one intriguing tweak, they might.
What's your version of "I'm getting stronger?"
How can less weight build more muscle?
For decades, physical therapists have been leveling up the muscle-building effects of lighter loads—especially in people recovering from an injury—using a technique called blood flow restriction (BFR) training.
Originating in 1960s Japan, BFR training uses cuffs placed high on the arms or legs to partially restrict venous blood flow away from the working muscles. This limits oxygen availability to the muscles, creating a hypoxic environment that increases metabolic stress and fatigue.
The low-oxygen environment can trigger:
Type II muscle fiber activation: Fast-twitch Type II muscle fibers are normally recruited during sprinting, jumping, and heavy lifting. They can function in lower-oxygen environments because they run on glucose. Selman calls Type II fibers our “most protective muscle” because they may help the body manage blood sugar and limit fat buildup.
Lactate accumulation: This creates that ‘feel the burn’ sensation, Selman explains. Lactate can temporarily spike human growth hormone, and while it doesn’t necessarily explain long-term muscle or strength gains, it may support recovery and metabolism.
In a sense, BFR is creating very similar physiological processes that happen during high-intensity training with heavy weights.
“The brain doesn’t know how heavy you just lifted.”
Suddenly, those light weights start to feel a lot more challenging, a lot more quickly.
A strength option for sore joints and fresh starts
BFR is mostly used in rehabilitation, but it’s made its way into athletics and performance recovery—LeBron James has been known to wear BFR cuffs. Selman is at the helm of bringing it to everyday fitness.
"Think about what they're using it for in physical therapy,” she says. “Look at how fast [people] build muscle. Why is that only good when someone comes out of knee surgery?"
She had only discovered it after being hit by years of pain and muscle loss following both a hip replacement and menopause. "I lost probably eight to ten pounds of muscle,” she says.
Selman is now interested in BFR’s potential for women in midlife, when the loss of estrogen can contribute to joint pain and make recovery from heavy load training feel more challenging. Estimates suggest that more than 50% of women experience joint pain or arthritis.
But beyond muscle, BFR may support bone health. A 2025 review in adults over 50 found that low-intensity BFR training improved bone mineral density more than low-intensity exercise alone. These effects were almost on par with heavy load training, but more studies are needed to confirm this.
And for adults who feel anxious about lifting heavy, light-intensity BFR might feel safer while still challenging muscles. As you gain strength, it could be a bridge to then helping you lift heavier. She explains: "Your brain won't let your muscles contract at a high level if it doesn't feel safe.”
What to know before trying BFR
The thought of reducing blood flow can sound alarming, and blood clot risks were an early concern. Selman says these fears are largely unfounded.
BFR partially limits blood flow out of the muscle, not to it. "That would be a terrible idea," she says.
Selman explains that when the body senses constriction, it creates an anticoagulant response that might support long-term cardiovascular health. In one large study, BFR users did report a slightly lower risk of blood clots than in the general population, but this is still not outright evidence.
It is also not right for everyone. People with vascular disease, uncontrolled hypertension, kidney disease, or a history of clots should check in with a doctor first.
The rundown: Is BFR or heavy weight more effective for muscle?
Heavy loads still have the edge for building maximum muscle strength, based on a review of 41 studies. But when it’s not practical—or if you’re looking for more variety in improving strength, strong bones, and recovery—BFR offers a science-backed alternative.
More research continues to show that strength isn’t just a byproduct of lifting heavy. The key is to challenge your muscles consistently and effectively, and work with your unique body.
“You don’t have to crush yourself and [do] CrossFit,” she says. “Just find what works for you that simplifies your life... make it just a part of your life so you can spend the rest of your time really focusing on life.”
Sample weekly routine
3x/week: BFR training (20-minute sessions) or another strength workout
1x/week: High-intensity interval training
Multiple times/week: Light, consistent daily movement—mobility, walking, Zone 2, or gardening
Stories I’m reading next:
The once-a-week workout is having a moment.
The gym is finally growing up.
Take action
Seli Strength is at the Livelong Women’s Health SummitTM! Catch Ashley in a session about The Science of Muscle, Midlife & Longevity. Tickets to the event are on sale now. Get them before prices increase.
Ruck x Livelong Media x mindbodygreen: Join us Friday, August 21 at 9:00 AM for a women’s ruck hosted by our friends at YVO Hamptons. Come move, connect, and experience one of the most approachable ways to build longevity into your routine. Sign up here
Earn CE credits: Members of the Livelong Women's Inner Circle™ can now earn 10 CE hours through Pinnacle Conference, LLC. Use code CECREDIT for $50 off your first year.
Make friends with women who enjoy women’s health: Join the Livelong Women’s Circle™.
Poll response
This question comes from last week’s newsletter: Can You Recreate a $15,000 Longevity Retreat at Home?
We asked: You’re checking into a retreat. What’s your first stop?
42% of you want to soak in the view, but for one reader, views are just the icing on the cake: “I love getting outside to feel the vibe and energy. Having a scenic spot to anchor this is a bonus.”
Personally, I’ve never seen a view like Mt. St. Helens in spring. Technically an active volcano, the colors of the flowers and new growth feel so striking against black volcanic rock.
Until next time!
Erin
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The information provided about wellness and health is for general informational and educational purposes only. We are not licensed medical professionals, and the content here should not be considered medical advice. Talk to a doctor before trying any of these suggestions.
