How to run faster – Triple Flexion #RunFormFriday

This is the most common question I hear. If I had to give only a one-phrase answer, then it is summed up to “optimizing triple flexion-triple extension”. Now what does that mean? Triple flexion-triple extension is the position of the legs during running. This position allows for optimal force production.

Triple Extension – Back power leg, Hip Extension, Knee Extension, Plantar Flexed Foot

Triple Flexion – Front Deceleration leg, Hip Flexion, Knee Flexion, Dorsiflexed foot

Run faster Triple Flexion

Anatomical model showing triple flexion (front leg) and triple extension (rear leg)

Many runners tend to run with reduced hip flexion (think ‘knee lift’) for a given pace. With insufficient hip flexion, in order for them to achieve the required stride length for a desired pace, they end up extending (straightening) the knee excessively just prior to foot contact. This puts them in a position where all they are able to do is over-stride, landing the foot out ahead of relatively more extended knee than is optimal. Usually at this point the athlete will be heel striking heavily, but some may still display a plantar flexed ankle and forefoot strike, especially if they’ve been consciously trying to work on ‘not heel striking’!

Regardless of pace or foot strike type, we look to enable a runner to land their foot under a flexing knee to promote improved running form.

From an adequate swing recovery position of triple flexion (hip flexion, knee flexion and ankle dorsiflexion) for a given running pace, the runner should be able to comfortably land the foot under a flexing knee, without conscious thought about contact position.

How To Work On This

1. Hip Flexor Stretching and Soft Tissue Massage (or Foam Rolling) – flexibility is important through the hip area, sitting lots reduces this.
2. Hip Mobility Routines (see here)
3. Glute Medius Activated
4. Core Activated (More specifically is the Transverse Abdominis needs to be fully activated) – exercises like dead bugs and moving planks
6. Resistance Training optimizing triple flexion and triple extension
7. Explosive training optimizing triple flexion and triple extension
8. Strength training to strengthen muscles needed to increase running leg power

Run faster Triple Flexion

Sprint starts are a great way of building explosive power – this is an extreme position, something you’d never get running a 5 or a 10k – but it will make getting to a fraction of that position “easy”

Something Important To Consider

Once I get runners familiar with the movement of combined hip and knee flexion bringing them into the recovery (foot under butt) position of swing phase, and they begin running in this way, the feedback is often that not only do they feel a lighter contact through not over-striding, but they can ALSO often feel an increase in Glute activity.

As always, I encourage your comments, experiences, and questions about cadence and technique in the comments section. See what’s up next week for our #RunFormFriday tip! For more in depth understanding on how to put this into practise, get in touch and we’ll see how we can help!

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I was an international swimmer both in the pool and open water between 17 and 21, and have been coaching swimming for 15 years now! Having raced as an age group triathlete, I've coached in triathlon since 2009.
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