How Can I Improve My Running Economy?
By Karen Hancock
Can I become a more efficient runner?
This is a question I’ve never been asked, which puzzles me. You ought to be curious about what you can do to become a more efficient and economical runner because running economy is the third of the 3 factors limiting your running speed . Differences in running economy can result in variations in race times between individuals of around 20%, after controlling for VO2 max differences. In case you’re still unconvinced, improving your economy will reduce your risk of hitting the wall in the marathon, and – of interest to fragile runners like me – it can even help prevent injuries.
What is running economy?
Your running economy is the oxygen cost of running at a particular speed. Strictly speaking, “efficiency” refers to work done per unit of energy, so “running economy” should be used to refer to oxygen consumption in relation to speed (which is not a measure of work). However, the terms are often used interchangeably. Think of your running economy as you would think about the fuel efficiency of your car. More economical runners burn less fuel and heat up less rapidly at any given pace than less economical runners and therefore can run faster, all other factors being equal. They also suffer less in hot conditions, and since they are more sparing of fuel, they are less likely to hit the wall in marathons.
Can I get my running economy measured?
If you’re having your VO2 max and LT measured in a lab on a treadmill, the resulting data can be graphed. A coach can compare athletes, who are likely to differ in terms of VO2 max, LT and their speeds at these levels, to give an idea of the relative strengths and weaknesses of her coachees. This will help her to tailor their training to their specific needs.
For the rest of us, who estimate our VO2 max pace from our 3-5k race pace, or in a Balke, Cooper or bleep test, it won’t be clear whether the reason we’re slower than our rivals is because our VO2 max is lower, or our running is less economical, or a combination of both. So to play safe, I would work on your running economy anyway, since many of the things you can do to improve economy can be worked on when not running. They can also reduce the risk of injury.
What can I do to improve mine?
Ideally, you should ensure:
- your running technique is mechanically efficient and doesn’t use unnecessary energy in moving forwards;
- you optimise the strength of your feet and legs to help them recruit as few muscle fibres as possible (which costs oxygen);
- you optimise flexibility in your Achilles tendons to maximise the elastic recoil (stored mechanical energy) which has no oxygen cost;
- you aren’t carrying unnecessary weight, either in the form of bodyweight or clothing; and
- you’re as race-fit as you can be.
Some of these things happen as by-products of your normal running training, but others require special attention, so here are the things you should work on.
Practise good running technique
Coaches disagree on whether it is worth attempting to modify the style of runners who appear to be running inefficiently. The research evidence shows that runners tend to pick a stride-length that is most efficient for their body, and that artificially changing it reduces economy. However, your style does become less efficient as you get more tired or tense. And some style ‘defects’ do seem to precipitate injury. So it is worth experimenting with your own, to see whether changes can reduce your perceived effort level at any given speed. Or have yourself videoed at a variety of running speeds, or near the finish of a race when your form is likely to deteriorate, and check the following points:
- Run tall, looking about 50m ahead; don’t hunch or lean. It helps if you consciously try to relax your face and shoulder muscles and lengthen your neck;
- Run lightly, rather than trying to dig holes in the road with your feet;
- Run with your elbows bent at 90 degrees (short levers move faster, and your legs will move faster as a result);
- The closer to a sprint you are aiming for, or the steeper the angle of ascent when running uphill, the more vigorously you should pump your arms;
- Don’t clench your fists or – conversely – allow your wrists to flap; and crucially;
- Focus on your technique when the going gets tough in races or training. Adjusting your technique may make you feel better than slowing down.
Good old-fashioned drills are exercises designed to encourage good running technique, so ask your coach about “High Knees”, “ Walking sprints”, “Fast Feet”, “Bum-Kicks” and other such delights if you feel yours needs attention.
Include hill-training in your schedule
If you choose medium (around 100-200m) hills with fairly steep inclines, you’ll improve your VO2 max, leg-strength and running technique, all at the same time. The best technique for running repetitions up hills of this sort – such as we practise at my Saturday morning sessions in Greenwich – is what I would describe as “neo-sprinting”. That is to say, you need to run head up (i.e. not watching your feet), using a high knee-lift, a powerful arm-drive, elbows moving close to your body and strong push-off from the toes. Aim to build up to 3 sets of 5 repetitions, with a jog back down recovery, and about 3-5 minutes jogging between sets. There’s a great deal to be said for doing a hills session once a week or fortnight, all year round.
Go to the gym
There’s now research evidence that gym-work – i.e. strength training, particularly of the legs - improves running economy. Various studies have suggested that following a 10-week programme using small numbers of repetitions (e.g. 3-5 sets of 5) at a fairly high resistance of such exercises as:
- parallel squats
- knee extensions
- knee flexions, and
- heel raises
increases running economy amongst fairly fit runners who were not currently doing gym-work. One study included upper-body strength work as well. That study measured the impact of a thrice-weekly programme of strength work (in female runners) as around 2%. The study which only evaluated the leg-strength programme measured the average increase in running economy as 13%, although it had no control group and was therefore not isolating the contribution of strength training alone. The studies conducted so far have been very small-scale. However, this evidence should persuade you to visit the gym more often – especially if taking days off from running makes you restless.
Stretching and flexibility work
Danish research has found that running economy can be almost doubled by improving the elastic energy return in the tendons in the legs. As you reach forward with your foot, your Achilles tendon stretches out. When your foot hits the ground and rolls forward onto your toes, the tendon snaps back to a shorter length, like a stretched elastic band which has been let go. This recoil has zero energy cost because it comes from the mechanical energy stored when your tendon was stretched out prior to footstrike. So, the more elastic recoil you can get in your tendons, the more efficient you’ll be. You can improve yours by running up hills, running on soft ground (sand-dunes are good), running barefoot, religiously stretching out your Achilles tendons and shunning high heels. But introduce these changes gradually, or you’ll get injured.
Reduce bodyweight and weight of clothing and footwear
Extra weight is more detrimental to your economy when added to the feet and legs. An extra 500g on each thigh increases the oxygen cost of running by 3.5% – that’s more than 6 minutes on a 3-hour marathon! But if it’s added to the feet, the cost goes up to 7.2% per 500g. My racing shoes weigh 43g less per shoe than my regular trainers. On this basis, I saved myself 1 minute and 13 seconds in my recent marathon (though the trade-off is that racing shoes increase the risk of injury). Remember that orthotics add to the weight of shoes and slow you down too.
Choose aerodynamic footwear and clothing
This is more important, the shorter and faster the race and the greater the windspeed – hence the premium placed on aerodynamic clothing by sprinters. In order of priority, choose: short hair, short socks, covered laces and tight-fitting Lycra clothing
Your running economy diminishes as you get more tired during a run. It can’t be alleviated by rehydrating or refuelling. The mechanism at work seems to be that repeated contractions of the muscles in the leg during running result in progressive muscle damage that reduces the power output of the muscles. This in turn results in reduced elastic recoil and therefore reduced economy. It becomes more difficult to regulate the stiffness of your legs to maximise rebound on foot strike. The onset of this phenomenon is most obvious when runners hit the wall in the marathon: they try to continue their progress with a deeper knee-bend at foot strike and more prolonged foot contact with the ground. Those who have experienced it often describe wobbliness or shakiness of the legs, or even losing control of their legs altogether. In extreme cases, runners appear to stagger about. The same process accounts for post-marathon stiffness. However, the onset of this type of fatigue can be delayed if you develop a sufficient base of endurance for your chosen event.
Things not to worry about
- Age – children are less efficient than adults – hence they tire more easily, but their efficiency improves steadily between ages of about 8 and 18. I’ve noticed that my 9-year–old son can now run in a straight line; last year he found it more difficult.
- Race – Africans and Asians use less energy than Caucasians, even when at zero speed – i.e. when sitting, standing or lying down.
Putting it into practice
After you’ve been running up hills, going to the gym, practising good technique and stretching your Achilles for a few weeks, find a suitable race. In your aerodynamic clothing and racing shoes, and in the middle of the race, as you’re wondering whether you can keep going at this pace, do a style-check: mentally work from your head down to your feet and make any improvements you can. I hope you’ll find it’ll help you through a tough patch without slowing too much. Let me know how you get on.
Level 2 Endurance Coach