By T.J. Murphy

Just 40 days before the 2014 Sochi Olympic Games, Todd Lodwick, an Olympic silver medalist in 2010 and one of the USA’s top Nordic skiers, suffered a crash, breaking several ribs and trashing a rotator cuff. First impressions were that his season was over. Yet when the U.S. team marched in the opening ceremonies, Lodwick was the flag bearer, even using his injured side to carry the flag. He raced in Sochi and finished his 6th Olympic Games.

The miraculous recovery was credited to the use of two-times-day blood flow restriction training overseen by Dr. Jim Stray-Gundersen, MD, a pioneer in BFR as well as high-low altitude training. The crash happened on a Friday and to prevent the wave of atrophy that injury immobilization traditional produces, Stray-Gundersen had Lodwick performing two BFR workouts a day. They monitored Lodwick’s progress through x-rays and watched the shoulder heal.

The origins of BFR suggest that Lodwick’s recovery shouldn’t have been a surprise. Developed in Japan about 50 years ago by Dr. Yoshiaki Sato, a Japanese sports scientist, BFR came about after Sato paid attention to the muscle fatigue he felt after sitting during a long funeral. He later reverse-engineered his observation and after he broke an ankle and injured a knee skiing, he experimented with bike tubes and judo belts to restrict blood flow to the muscles while he wore a cast. When he went in to have the cast changed—a ritual procedure because casts shrink the encased muscle via atrophy—Sato’s doctors were shocked to see a ready-to-go set of leg muscles at full size. Sato figured he was onto something. In the ensuing decades he developed and fine-tuned BFR training into something that athletes can use for a variety of reasons, not to mention anyone who doesn’t want to get under a heavy barbell to strength train.

Basically, BFR works like this: Using a BFR unit like B Strong, you restrict blood flow to a target complex of muscles, bones and tissues. Using body weight or a light dumbbell, the athlete moves the limb and joint through a range of motion to exercise. Even though the resistance is light, a “metabolic crisis” is triggered. Two types of stimulation occur. Locally, the lack of blood flow to an area trying to do work initiates protein synthesis as the cells involved try to adapt to the stress. And second, more big picture, the central nervous system picks up on the metabolic crisis and goes to work trying to repair things. The athlete may be lifting a three-pound dumbbell with his arm, but he starts to sweat and gasp. “Well out of proportion to the work being done,” Stray-Gundersen said on the Institute of Human and Machine Cognition podcast, STEM-Talk. A signal is being sent that “all hell is breaking loose.”

So let’s cut to the chase.

What’s going on that may be of value to triathletes, either those simply trying to increase strength and power or those who are rehabbing? The metabolic crisis triggers slow-twitch muscle fibers first but soon begins recruiting large percentages of (and hence training) fast-twitch fibers, despite the light resistance. Studies have indicated that a range of potent factors are involved. Plasma growth hormone ramps up, mTor signaling pathways are activated in ways favorable to muscle growth and, remarkably, stem-cells are recruited and activated. Studies have confirmed that more muscles and muscle-fiber types are activated and that bone strength also responds. According to Stray-Gundersen, a study is now looking at whether or not ligaments also respond to the stimulus by getting stronger. “There’s a cascade of hormones stimulated from the brain facilitating the repair process.”

The potential values for the endurance athlete are several. For those wanting the hormonal and body composition benefits of heavy weight lifting but are afraid of injury, BFR, if done properly with the right equipment, offers a safer alternative. For the injured triathlete, use of BFR can mitigate atrophy and speed one’s return to training and racing.

Another value is for older triathletes wanting to buffer age-related loss of lean muscle mass, in particular fast-twitch fibers that key to explosive power and speed. BFR has been described by its founder as a form of anti-aging medicine, and the research is backing the claim.

A word of caution: When it comes to BFR equipment, the internet is awash with all sorts of gadgetry that may at best be in effective and at worst dangerous. Go to (affiliated with Stray-Gundersen) or (affiliated with Dr. Sato) for the tech and how to use it properly.

For more reporting on BFR, visit for for a story about what it’s like to do BFR and what the immediate impact is.