swiss ball squat

Unstable Training: a Waste of Time?

Learn what science and experience have to say about unstable surface training

I’ve enjoyed working as a trainer and nutrition consultant for nearly 30 years now. Being in the commercial gym setting, it’s inevitable we coaches enjoy seeing the masses interpret the dogma that plagues our industry.

Social media to muscle mags are an infinite source of misinformation- but with the right photo model and editor, we can make pretty much anything seem good on paper.

One of my biggest pet peeves is coming into the gym and finding some misguided soul balancing on a BOSU while attempting curls to deadlifts- the reasoning we are told is, “…to engage the core while developing target muscles..”. <sigh>

For those of you that have spent any appreciable time with coach Poliquin know the Strength Sensei is famous for  his clinical pearls. Two key ones that come to mind in this setting: “If you only got one ass, you can’t sit on two horses” – or in other words pick your training priority and focus on it. . . and : “Training on the BOSU makes you good at the BOSU”– or in other words, if you want to get good at curls and deadlifts, do curls and deadlifts. If you want to engage your core, target it directly and if you want to be good at standing on the BOSU, practice just that.

Attempting to do all three at once prevents you from  any appreciable success at any of them.

I know it’s common sense to the educated coach, but clearly, the masses remain motivated, and well read . . . just poor choices of reference. As such I wanted to grab just a few studies that you as a coach or supportive workout partner may want to slip “Bosu Bob”.


Activation Of Core Musculature During Exercise With Stable And Unstable Loads On Stable And Unstable Surfaces

 Flanagan, Sean; Kohler, James M; Whiting, William C
Journal of Strength & Conditioning Research. 24():1, January 2010.
doi: 10.1097/01.JSC.0000367107.20908.b4

“…Greater activation of the core musculature appears to occur by lifting a heavier weight overhead than by lifting a lighter weight overhead either with an unstable load or on an unstable surface.”

Or in other words, you want a strong core ? Master pressing big weights in full control overhead, not a lighter weight while wobbling


Muscle Activation Patterns While Lifting Stable and Unstable Loads on Stable and Unstable Surfaces

Kohler, James M; Flanagan, Sean P; Whiting, William C
Journal of Strength & Conditioning Research. 24(2):313-321, February 2010.
doi: 10.1519/JSC.0b013e3181c8655a

“…The findings provide little support for training with a lighter load using unstable loads or unstable surfaces.”

In this case, many of you may have seen the client using a ‘shaky-weight’ while standing on a BOSU or the like- the authors clearly point to a lack of advantage using either unstable loads or unstable surfaces


Deadlift Muscle Force and Activation Under Stable and Unstable Conditions

Chulvi-Medrano, Iván; García-Massó, Xavier; Colado, Juan C; Pablos, Carlos; de Moraes, Joao Alves; Fuster, Maria Journal of Strength & Conditioning Research. 24(10):2723-2730, October 2010.
doi: 10.1519/JSC.0b013e3181f0a8b9

“…Therefore, we conclude that the use of instability devices in deadlift training does not increase performance, nor does it provide greater activation of the paraspinal muscles, leading us to question their value in the performance of other types of exercises.”

So here it’s made clear that if maximal development of the paraspinal muscles from deadlifting is your goal, you’re better off lifting a large load on the ground than a miniscule pull on a wobbly surface [remember one ass, one horse ?]


Not All Instability Training Devices Enhance Muscle Activation in Highly Resistance-Trained Individuals

Wahl, Michael J; Behm, David G
Journal of Strength & Conditioning Research. 22(4):1360-1370, July 2008.
doi: 10.1519/JSC.0b013e318175ca3c

“…These results indicate that the use of moderately unstable training devices (i.e., Dyna Disc, BOSU ball) did not provide sufficient challenges to the neuromuscular system in highly resistance-trained individuals. Since highly trained individuals may already possess enhanced stability from the use of dynamic free weights, a greater degree of instability may be necessary.”

This last study is fascinating in that it is almost backwards. Highly trained individuals who had developed significant strength training conventionally, enjoyed enhanced stability going in to try their hand at BOSU or the such, AND thanks to their inherent strength and intramuscular coordination from lifting large loads, things weren’t “wobbly enough” to challenge their neuromuscular system sufficiently .

If we were to leave you with one big take home message, it’s that success leaves clues. If you were to look to the protocols designed by today’s most successful strength coaches, none of note are designing phases to be done on unstable surfaces. Glancing around the gym, no one will see any of the top physiques standing like a weather-vein on a wobble board.

If your goal is big arms, do your curls uninhibited on solid ground but with decent weights for strict form. Same goes for your deadlift, etc. Core activation is strongest when supporting large loads over head, but if you want to get good at standing on the BOSU, remember that is the only appreciable outcome.


Mike Demeter has been a Trainer for 30 years, serving nearly 25 of those as Senior Trainer with giant Canadian chain GoodLife Fitness. Mike is a certified trainer in coach Poliquin’s system as well as a Metabolic Analytics  practioner, in addition to a litany of specialty courses under the tutelage of the Strength Sensei. Mike maintains an informative FB page at: and can be reached there for online training or coaching enquiries.

Mike Demeter
Coach Demeter, preaching by example…