I’m a runner. Should I stretch? Some thoughts from Sarah Young, of Adapt Physiotherapy.

While there are some instances where stretching can be helpful, for the most part, you’re better off becoming stiffer.

To be an efficient runner, I would argue the two most import things are:

1. That you have ‘stiff’ legs – what I mean here is that when you land, your knees don’t bend too much and your hips don’t sink down. When this happens, you’ve lost energy to the ground, rather than it pushing you forwards. Stiffness comes from strong muscles and good plyometric strength (Basic Plyometric Drills for Runners). It also comes from practising having stiff legs – watch Sarah’s video for some ideas. Including stilt walks, leaning towers and pogo bounce.
2. That your foot lands under your body, and not in front of it. You can have stiff legs and springy legs but if your foot isn’t under your body when you land, you can’t use that stiffness at all. It’s wasted.

So, for both of these two things, flexibility serves absolutely no benefit, and may in fact do the opposite. So instead of stretching practise getting stiff!

By way of explanation: Sources
Runners World UK,
Training Peaks Blog
Stryd Blog

As scientific expressions go, ‘running economy’ (RE) has never been as familiar to runners as the terms ‘VO₂ max’ and ‘lactate threshold’.But now, many exercise scientists consider RE to be the third critical determinant of distance running performance.  In simple terms, VO₂ max is your upper limit of oxygen consumption (your aerobic capacity), lactate threshold is the level of your aerobic capacity that you can sustain for a long time, and running economy (RE) is your efficiency at converting that oxygen consumption into forward motion. For any given pace, the less energy and oxygen you use, the better. So, what factors can affect an individual’s RE, and how can you improve yours?

Among reasonably fit runners and walkers showing typical variations in flexibility, it appears that the less flexible ones are more economical on average. This somewhat surprising trend has been explained as a possible consequence of two factors: stiff joints need less muscle force (and thus less energy) to stabilise them; and stiff muscle-tendon units provide superior elastic storage and energy return from foot-strike to push-off.  These are the springs in your legs that give you free propulsion! It’s possible that, for distance runners, medium flexibility is preferable to very low flexibility (which increases the incidence of injury due to limited range of motion) or very high flexibility (which seems to worsen RE).

The degree of stiffness in muscle-tendon units is referred to as Leg Spring Stiffness (LSS). Stiff muscles and tendons are able to recoil more elastic energy upon landing, and so it follows that runners with a higher LSS will use less energy and oxygen at a given speed thus improving their running economy (RE).