Flexion Inspection: How Long Do You Sit Down Every Day?

I had a really interesting chat with Ironman athlete and Physiotherapist Claire Doherty (@Claired0) earlier today, regarding glute activation in runners. In particular the importance of being able to run with adequate hip extension to facilitate Glute.Max. activation.

Mo Farah Hip ExtensionWhat Limits Your Glute Activation?

In stark contract to the image here (right) of Mo Farah in full flow, showing fantastic hip extension – so many of the athletes we meet single every day barely achieve zero degrees hip extension.

It’s important to view running as an extension pattern, with the triple extension of hip, knee and ankle driving us forwards stride by stride, during stance phase of gait. Particularly Glute.Max. is vitally important in it’s role of creating a powerful drive of the leg, backwards against the ground – pushing us forward.

In terms of antagonistic relationships; overactivity and shortening in hip flexor muscles such as Rectus Femoris, Psoas, Iliacus, Tensor Fascia Lata, and even Sartorius can all act to inhibit a runner’s ability to extend the hip and utilise Glute.Max.


What can affect this overactivity and shortening in the hip flexor complex?

Numerous factors, of course – but one significant factor is time spent sitting, or variations thereof (cycling, driving, etc…).

Benjamin SittingThe various seated postures we get ourselves into on a daily basis, are just about the direct opposite in terms of movement patterning to running!

Sitting is a static flexion pattern…

Running is a dynamic extension pattern…

I’m often quick to point out to runners and triathletes that if you spend time reinforcing this flexion pattern (which is essentially what you’re doing with 9hrs at a desk every day!), then your ability to extend the hip will probably suffer – and as such also your running glute activation, lumbro-pelvic muscle balance, and stride length.

Put simply – excessive time spent seated, while often unavoidable (I’m slouched on a chair as I type this), isn’t going to do your running, or indeed your butt, any good!

Two Suggestions!

1. Record Your Time Spent Sitting For 1 Week

This is Claire’s brilliant idea… I had to share it!

Keep a simple diary. Much like a food diary, but recording the time you spend sitting down every day. Every single form of seated activity, from working at a desk to cycling.

If you’re anything like me, the results will be ALARMING.

2. Offset Time Spent In Flexion With Specific Extension Exercises

I’m a realist. I get that much of 21st century living requires sitting – not to mention the leisure activities we engage in. Cycling for instance.

I usually suggest for every two hours spent in a flexion pattern, athletes should get up, and spend 5mins working on extension exercises such as hip flexor stretches and glute activations.

Image via Benjamin Thompson

About The Author 

James has an academic background in Sport Rehabilitation and a special interest in Applied Biomechanics. He currently coaches a large number of Runners and Triathletes across all levels of ability and performance. He's grown a strong reputation for enabling athletes to improve their running performance and overcome running injuries through improving their Running Technique and developing Running Specific Strength.



  • […] The author is James Dunne and he’s a rehab and biomechanics expert. His recent post is Flexion Inspection: How Long Do You Sit Down Each Day? He discusses the perils of setting, namely tight hip flexors that inhibit the glutes and thus […]

  • Would this be a cause of lower leg circumduction during a run? If so what is the best exercise for such and how long to improve it?

  • I have just altered both my work and home desks to include a standing position. I am lucky to be exactly the right height to be able to use a three drawer filing cabinet as a standing desk (yeah, I know, vertically challenged), and have raised second monitors to eye height for each of these.

    So from being desk-seated for at least 8 hours a day, I now sit for less than two (usually at meetings). One big advantage of a standing desk is that you rarely stand still, you pace, rock, shuffle, stretch……

    This may help others, if you can manage it.

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