How Can l Run Faster?


Trying to run faster without the gym.  Kidding yourself?

After a couple of years of running you can run at a 5 minute per kilometre pace for 10 kms. In the next 18 months you want to run that under a 4 min/km pace. You usually run between 8 and 10 km a couple of times a week and have had a couple of small niggles along your running journey, but nothing major. You figure you will just progress your running speed gradually by throwing in some interval work and keeping up with a home exercise programme to strengthen your glutes and calves. Will it work ?

To answer this question we need to think about what actually happens when your body improves at running and your times get faster.  But first, bare with me while I   go through some jargon.   Suffice to say,  If your improved speed is just down to improved aerobic endurance and not improvements in strength or power then this could be a limiting factor for you.

JARGON OF TRAINING

Aerobic endurance is a measure of your bodies ability to take oxygen from the atmosphere and use it to help power your muscles. Your maximum oxygen consumption is your VO2 max and is a common measure of fitness. Another measure is the lactate threshold. This is a measure of the point that lactate starts to accumulate because your body can’t remove it faster than it generates it, leading to other byproducts culminating in muscle fatigue.  Lactate is a byproduct of using glycogen (from the sugars you eat) to generate energy.  You can improve your lactate threshold and V02 max with exercise (2).

Strength is the amount of force you can apply to an object or the ground (1).  When you run, the muscles act within very short ranges of motion and transfer high amount of force to the tendons to propel you forward.

Power relates to the work done to move your body and relates to the rate you can generate force when moving a given load – the ‘rate of force development’ (3). This is essential to acceleration and running speed. Faster runners have longer strides, shorter ground contact times and more effective turnover, helping them get to that next stride quicker, while maintaining a full stride length.  They also maintain soft landings, effectively decelerating and absorbing forces in multiple directions, rather than the heavy landings which have been associated with overuse injuries (4).

When thinking about power, we need to also think about the stretch shortening cycle (SSC) which relates to the interplay between the muscle, tendon and connective tissue around it. When you strike the ground during running the muscles of the leg contract, while the leg stays mostly stiff (particularly the quads, gastroc and soleus). This causes a lengthening of the corresponding tendons, and if timed correctly, a spring like recoil effect. There is a complex co-ordination and if there is too much force to control, or conversely too little, you might not get the spring.  Activities which are slow SSC involve ground contact times of over 250 milliseconds, fast SCC is anything faster than that. Sprinting ground contact can be as low as 80-100 milliseconds in athletes (3,5,6).

Plyometric training and jump training are types of power training which focus on developing stiffer and more springy tendons. We will get to that soon.

TRAINING OPTIONS

To improve your running speeds over 10 km we are looking at improving your overall running efficiency- which is a combination of all the factors noted above. Running in itself will help you develop strength and rate of force development to a limited extent. How close you will get to that 4 min goal before you need gym work will vary significantly between individuals.  You are aiming to average 15 km an hour over 10 kilometre’s, here are a few ideas to consider on your journey-

SIMPLE JUMP PROGRESSION  (Flanagan & Comyns, 2008)

  1. 1st phase is mastering the landing. Quiet landings.
  2. Springy jumps like skipping, focussing on leg stiffness. Legs stiff like springs, staying on balls of feet.
  3. Next start adding hurdles or a height element. Jump high, Jump fast.
  4. Lastly, when ready, adding depth jumps. Jumping from a height and then using the elastic energy in landing to recoil into a higher jump. You need to make sure that you are ready for this phase.  Progressing too early through any of these phases will mean slower improvements.

Take your time with this sort of programme.  The literature suggests at-least 10 weeks for a strength training programme to improve your rate of force development.  However, some adaptation in plyometrics will take more than 4 months to achieve (1). It isn’t just muscles adapting, it is the tendon and the other connective tissue. Additionally, if you are really serious, you may need to reduce the volume of your running training for a period of time. It is known that concurrent training of strength and endurance can negatively impact on strength gains (2).

In general you need to consider the Stretch shortening cycle (SSC) duration of the activity you are training for. However, there are benefits of including different duration movements in your programme.  Here are some examples to illustrate.

Additional Physio tips

 

A FINAL THOUGHT

Given there is only so much time in a day, why waste your effort doing ineffective exercises. If your Physio reckons you can do more in the gym, then this is also a quicker way to finish your rehab and get back to doing what you want to do or get around the track a bit faster.

 

Christopher Bentley is an experienced physiotherapist who works at our Melbourne CBD clinic and Diamond Creek clinics.