The fitness industry is full of coaches, trainers, experts and influencers all attempting to pass on their knowledge to help us make the most of our workouts to get fitter, stronger and healthier. And, because we deem these ‘experts’ to be speaking from a position of authority and knowledge, we blindly follow them – which as we’ve discussed before, can have disastrous effects.
So, what if we told you that there is a much more effective way to perform bicep curls, squats and other press and lift movements to enhance muscle growth; and one that we’d argue you’ve never heard of or thought about before?
According to fitness coach and founder of Advanced Human Performance Dr Joel Seedman – who has previously informed us of the best deadlift we’ve never done – there is and it all revolves around 90-degree angles.
Taking to Instagram with a few videos for demonstration – and further information provided on his website – Joel says the 90-degree joint angle is a “hidden training secret” and one the “fitness industry has kept silent on for decades.”
In his Instagram Reels, Joel adds, “Much of what is currently advocated & employed in the fitness industry is not based on science or research. Instead, it’s based on what coaches have been implementing for decades, not because it’s best but simply because it’s how they were taught because that’s how their coaches before them were also taught.”
“When we examine sub-sciences of kinesiology including structural muscle physiology, biomechanics, neuromuscular physiology, physics & more, we see that optimal range of motion for most movements involve 90-degree joint angles.”
“The concept that more is better & that max ROM (range of motion, which generally speaking is not currently what’s used) is not only NOT based on science but in fact goes against every element of science we know.”
“We never want max of anything in physiology including hormones, enzymes, chemicals, reactions & yes, even range of motion. Instead, we want the optimal level. That optimal level is 90-degrees.”
Why does Dr Seedman claim 90-degrees is optimal, then?
“90-degrees maximises muscles activation, strength gains, muscle hypertrophy, joint health & athletic performance, not to mention full-body stability, mobility, symmetry & more.”
“Just because something works and has been done a certain way for decades doesn’t mean it’s optimal. Good is the enemy of best.”
In some further information on his website, Dr Seedman explains how to use the 90-degree angle when performing squats. He says, “an optimal squat involves approximately 90-degree joint angles. This is typically 10-30 degrees above parallel.”
“The type of squat and loading position will tend to dictate how close a 90-degree joint angle and parallel squat are to each other. Typically, a 90-degree barbell back squat will be moderately above parallel, whereas a 90-degree front-loaded squat will be closer to parallel.”
In the case of bicep curls, we’re typically told to curl the bar, dumbbells or whatever other weight we’re lifting, up towards our chin. As in, we should start with our arms down in front of us, and curl the weight through a range of 180-degrees until our hands are underneath our chin.
Joel says this isn’t optimal and that using a 90-degree form “maximises cross bridges,” – the term used to define how our muscles actually contract during a lift or press – “which ultimately dictates the level of motor unit recruitment and how well we stimulate the muscle for strength & hypertrophy adaptations.”
It’s a big idea put forward by Joel, but one that appears to be able to back up through years of research and real world case studies. It’s certainly a simple training technique to employ next time you’re in the gym, so why not give it a go and see if you notice a quicker increase in muscular size.
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