The Never-Ending debate – Full Range of Motion vs. 90-degrees

The Never-Ending Debate: Full Range of Motion vs. 90-degrees


During your fitness career, you may at some point have heard the saying “Ass to Grass,” when a trainer or athlete is talking about the expected range of motion in a squat. This saying refers to an individual’s hamstrings (back of thighs) resting onto their calves in their squat movement. In fact, this range of motion is a requirement for Powerlifters while competing, and anything less than this is not considered a clean repetition. Essentially, competition standards require the lifter to lift as much weight as possible, while going through the movement’s full range of motion.

The full-range of motion ‘hype’ has been discussed and promoted for many other exercises and movements, and does have scientific-merit behind it.


HOWEVER, recently there has also been a push in the fitness industry of an opinion that a 90- degree angle in a joint is the optimal angle to be squatting, pulling, pressing, or hinging to – no less and no more. You can try this right now – bend your elbow to 90 degrees, then lean your torso forward to 90 degrees between thighs and belly, then squat down so that your knee reaches 90 degrees. What you will find is that it much less movement than what each of those areas is capable of moving through. Yet, this opinion is also backed with science-based literature stating that this angle will not only optimize strength gains, but is also important for the health of one’s joints.


SO…. Which one is superior? What is our opinion here at Thrive?

Well, though this is not always the way to do things, we are of the “sit on the fence” mindset. We incorporate both opinions into the training of our clients, and here is why:


Let’s start with the benefits of going through a joint’s full range of motion. Within a single repetition of an exercise, many different components of your musculoskeletal system (musculo= muscle, skeletal = skeleton) are involved. Your bone, muscle, and connective tissues (fascia, tendons, ligaments) all have some degree of blood supply that allows for the delivery of oxygen, nutrients, and the removal of waste products. Bone and muscle have very good blood supply, allowing for quick healing, recovery, and a large capacity for work. Tendons and ligaments have less of a blood supply, which means that injuries to these areas take longer to heal. Cartilage on the other hand, lacks its own blood supply, and must depend on a ‘pumping action’ from nearby fluid in order to receive any oxygen or nutrients. By moving a joint through its full range of motion, and under a certain resistance (whether that’s bodyweight or weighted), these connective tissues (ligaments, tendons, fascia, and cartilage) are able to maintain their viability.

This science applies to anyone, no matter their age. As an athlete, having strong, resilient tissues is vital to injury risk prevention. There are many in-game scenarios where the body is placed in vulnerable positions, and lack of full range of motion can increase one’s susceptibility to injury. This idea also has a large impact on joint health longevity during the aging process. Our Westernized culture has slowly made the aging process more accelerated. Middle-aged adults move as though they are decades older, and older adults lose their autonomy at an earlier age. However, in other areas of the world – the aging process, is something of a myth. Numerous researchers who have immersed themselves in Eastern cultures find that the older adult population moves with the same fluency and ease as their younger counterparts. One example comes from a researcher named Dan Buettner, who lived with a 100-year old Okinawan woman, and observed her getting up and down off the ground 30-40 times each day!! How many times do you do that? This type of movement requires full range of motion through many joints.

This is our mentality when we program exercises that take clients through their joints’ full range of motion. In the gym, exercise is controlled and predictable. Out in the “real world,” one wrong step off the curb or the sidewalk can force the body into a position where the difference between an injury and a close call is the strength, range, and vitality of your joints.


Now to the other side of this fence. Recently, many of our clients have shown an increased interest in performance-based goals. For many exercises, these goals are based on the load being lifted within the set. Heavy (relative to an individual) resistance training has proven to have profound positive effects on our whole-body health. It increases the release of essential muscle-building hormones, increases muscle strength and injury-resiliency, it can stimulate bone formation and strength, and it improves the mind-muscle connection to allow for better muscle recruitment. With this in mind, many of our clients have made it their mission to progressively increase their weights, and are motivated by constant improvement in this realm. When attempting to lift heavier loads, safety is our number one priority. This not only includes the safety of the client as a whole, but the safety of the individual’s joints as they attempt this heavier weight. It is true that as the intensity of the exercise increases, the risk for injury also increases. With this in mind, we coach these lifts with the 90-degree standard. That is, attempt to reach a 90-degree angle in the primary movement joint (elbow for upper body, knee for squat, hips for hinging) with the weight you are using. The research conducted supporting this opinion includes not only quantitative data, but qualitative data from those who have utilized this technique. The consensus for many high-performance athletes and the general population is that when using heavier loads and multiple muscle groups, the 90-degree method feels safer, and protects certain joints from injury or re-injury while completing a lift.


In our opinion here at Thrive, both of these methods have a place in an individual’s fitness program. No matter a client’s age or fitness level, we do our best to employ both methods often in our programs. We encourage clients to attain their fullest range of motion in many exercises, primarily when the load being used is lower. This ensures that our clients can maintain (and improve) their movement abilities in everyday, unpredictable activities, and gives them the confidence to handle whatever “the real world” throws at them. When a client shows interest in lifting a heavier weight, we emphasize and coach the 90-degree standard as a way to ensure their safety, while still maximizing strength gains.

To us, there is no right answer. Both have their place in the gym. The best thing we can do for you is make you feel better, and to have the confidence to go through your day as your strongest, most resilient-self. And we will work with you to get you there.