If you've ever been to one of our body conditioning classes, you'll know we like to de-stabilise just about everything... Why do a developpe when you can do a developpe on a wobble board? Why do a squat jump when you can do a squat jump on a BOSU trainer? Why do a glute bridge when.... Well, you get the picture.
It turns out we're not alone in this obsession. In fact, researchers at the Universities of York and Windsor have taken things to the next level, by comparing the effects of destabilising the body from the bottom up, vs the top down.
To create these two types of instability they used either a BOSU trainer to destabilise the lower body, or a water-filled cylinder called an ATTITUBE to destabilise the upper body.
Study participants were then adorned with 75 reflective markers, to track kinematics of the ankle, knee, hip and trunk, and electrical recordings of muscle activity were also taken from 12 muscles around the body. Participants were recorded performing three different types of squat: Type 1) Holding an Olympic bar across their shoulders and standing on a stable surface (the floor), Type 2) Holding an Olympic bar across their shoulders and standing on a destabilised surface (the BOSU trainer), Type 3) Holding an ATTITUBE on their shoulders and standing on a stable surface (the floor).
And the results did indeed show a difference in movement pathways and muscle activation during the different squat types. Destabilising the body from the top down resulted in participants squatting with a flatter back (one of the hallmarks of good squat technique), thereby reducing the load through the erector spinae muscles, and increasing activation of the abdominals and obliques. Destabilising the body from the bottom up, in contrast, resulted in greater activation of the calf, hamstrings and quads, while increasing movement through the knee and ankle joints.
While this was a small study, I am in agreement with the authors that it provides valuable information for teaching advanced squat technique, as well as for potential rehabilitation scenarios. I would also add that it really drives the message home that when it comes to workouts, variety is the spice of life. Keep trying new things and challenging your body in as many different ways as you can!
So now I am left with only two questions... 1) Where can I buy one of the tubes?! And 2) I wonder what happens if you try and squat both at once...
Beth Jones, PhD. xx
Source: Nairn et al. J Strength Cond Res 2016; EPub Ahead of Print - Motion and muscle activity are affected by instability location during a squat exercise.