BFR AND BMR | NUTRITION & DIETETICS|L-6|

What Is Blood Flow Restriction (BFR) Training?

A new training technique that embraces the concept of working out “smarter, not harder” allows you to exercise at a lower intensity and still make progress.

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The method is called blood flow restriction (BFR) training — and it’s exactly what it sounds like.

“A special kind of tourniquet (elastic band) goes around your thigh or arm to reduce the blood flow out of that area,” says physical therapist Meghan Brady, DPT, who is certified in BFR. “It tricks your body into thinking you’re working harder than you are.”

The result? You can use less weight to build strength and muscle mass.

“BFR training can be a great addition to your fitness routine, especially during an active recovery week,” she continues. “It’s also helpful for people who can’t lift enough weight to support muscle growth, like people with osteoporosis or those undergoing surgery.”

To explain the basics of BFR, or occlusion training, let’s hear more from Brady, as well as exercise physiologist Chris Dempers, EP-C, and certified personal trainer Michael Bellace, C-PT.

How does restrictive blood flow training work?

The idea of “no pain, no gain” isn’t too far off from what science tells us about the process of muscle growth, or muscle hypertrophy. When you strength train, you change the environment inside your muscles and this activates muscle hypertrophy.

Muscle growth happens through:

Muscle trauma: To get bigger muscles, you have to stress them enough to injure the muscle fibers. The amount of weight or resistance required to do this depends on your fitness level. Once muscles are damaged, your body gets to work repairing and rebuilding them. That leads to larger and stronger muscles.

Basal metabolic rate (BMR) is the rate of energy expenditure per unit time by endothermic animals at rest.[1] It is reported in energy units per unit time ranging from watt (joule/second) to ml O2/min or joule per hour per kg body mass J/(h·kg). Proper measurement requires a strict set of criteria to be met. These criteria include being in a physically and psychologically undisturbed state and being in a thermally neutral environment while in the post-absorptive state (i.e., not actively digesting food).[1] In bradymetabolic animals, such as fish and reptiles, the equivalent term standard metabolic rate (SMR) applies. It follows the same criteria as BMR, but requires the documentation of the temperature at which the metabolic rate was measured. This makes BMR a variant of standard metabolic rate measurement that excludes the temperature data, a practice that has led to problems in defining “standard” rates of metabolism for many mammals.[1]

Metabolism comprises the processes that the body needs to function.[2] Basal metabolic rate is the amount of energy per unit of time that a person needs to keep the body functioning at rest. Some of those processes are breathing, blood circulation, controlling body temperature, cell growth, brain and nerve function, and contraction of muscles. Basal metabolic rate affects the rate that a person burns calories and ultimately whether that individual maintains, gains, or loses weight.

Description

The body’s generation of heat is known as thermogenesis and it can be measured to determine the amount of energy expended. BMR generally decreases with age, and with the decrease in lean body mass (as may happen with aging). Increasing muscle mass has the effect of increasing BMR. Aerobic (resistance) fitness level, a product of cardiovascular exercise, while previously thought to have effect on BMR, has been shown in the 1990s not to correlate with BMR when adjusted for fat-free body mass.[citation needed] But anaerobic exercise does increase resting energy consumption (see “aerobic vs. anaerobic exercise”).[5] Illness, previously consumed food and beverages, environmental temperature, and stress levels can affect one’s overall energy expenditure as well as one’s BMR.