Practical guide on how to identify your own dominant side and bring the other side up to par

The ambidextrous athlete: by working on your non-dominant leg you can improve your symmetry and your speed

My cat Tigger is left-handed: when my three-year-old daughter Sabrina lines up Tigger’s fortified tuna pieces in a straight row and his left leg accelerates forwards, over and over again, to pull each morsel into optimal eating position beneath his snout, I know that Tigger is laterally asymmetrical. For the key act of food acquisition, he relies totally on his left leg, even though his two appendages appear to be carbon copies of each other. His apparent symmetry is clearly an illusion.

Fiddler crabs, for example, possess a smaller claw which is used for grooming, grasping, and cutting, and a larger, stronger claw which works well for courtship and acrobatic displays. In one species of fiddler crab, Uca vocans, all males are right-claw dominant. It’s a different story for the American lobster (Homarus americanus); these decapods also exhibit ’clawedness’, but about 50% are right-claw dominant, while the other half favour the left claw.

It’s not known for certain whether cows exhibit ’hoofedness’, but it is well known that cowhides have different thicknesses on the right and left sides. Taking lateralism to extremes, it appears that some fish have two right - or left - eyes rather than one of each.

Humans, of course, are not immune to asymmetry. If you are a typical example of Homo sapiens, your right ear is a little lower than your left and your right hand and foot a little bigger than the left ones. If you are a male, your right testicle is larger and heavier - yet hangs higher - than the left one; if you are female, your right ovary probably outsizes your left one.

Beyond these anatomical asymmetries lie the curious behavioural ones. When asked to turn around, women tend to move to the left, while men rotate to the right. Language is controlled by the left hemisphere of the human brain, while spatial and emotional behaviours emerge from the right hemisphere. As you are well aware, human beings tend to have a ’favourite’ hand which they use preferentially both for heavy physical tasks and tasks which require great dexterity. This favoured hand is called upon for such disparate activities as throwing, writing, bowling, punching, and performing micro-surgery. While the existence of hand preferences is common knowledge, what is less widely known is that humans also exhibit ’eyedness’, ’earedness’, and ’footedness’ - that is, we all tend to have a favourite eye, ear, and foot.

You could observe footedness first-hand if you assembled a large group of people in a straight line and simply asked them to step forward: About 56% of your subjects would always step forward with the right foot, 22% would favour the left foot, and the remaining 22% would exhibit no foot preference: in other words, they would be equally likely to step forward with either foot (1). The right foot appears to be the favourite foot, at least when it comes to stepping forward.

Footedness in running

It is also easy to observe footedness in a running setting. If you replay a videotape of the 100m Olympic final - or even a local track meet - you will see that at the start of the race, most of the athletes are in the blocks with their right feet back. At the gun, they explode up and out, and it is the right foot that swings forwards first and makes the initial contact with the track. The same scenario occurs in speed skating; speed skaters tend to begin their races with their right feet back but then explode forwards with their right legs as the competition begins. Are these athletes making the first forward leg swing a right one because their right legs are stronger/more powerful - or because their right legs are weaker?

That’s a tough question, but if we are talking about push-off strength and power, ie strength and power created when the leg is in contact with the ground, then the right leg may indeed be the weaker appendage. Some research suggests that the left foot and leg are probably stronger than their right counterparts in about 90% of the population.

Why should this be true? Well, since most people are more dextrous with their dextral hand (note that the word dextrous, which means finely-coordinated, has the same root as dextral, which means right), when they are forced to make a choice of feet they tend to ’default’ to the right foot. If you put a group of young people on the football pitch, for example, and ask them to use one of their feet to volley a football out of mid-air, about 90% will thrust their right legs forwards. People sense intuitively that their right sides are dominant, so they tend to choose the right foot and leg to carry out an action when given a choice.

However, note that when a football is tossed with the right hand, a punch is thrown with the right hand, or a football is kicked with the right foot, it is the left leg and foot which must bear the weight and provide balance and co-ordination for the body. Therefore, in right-handed people it is natural for the left leg to become stronger than the right. Thus it is not surprising that when you ask people to ’just stand around’, body weight is not equally distributed between the legs; most people place more weight on their left leg and foot than on their right. The left leg is the strong support leg. This explains why most people take the first step up a flight of stairs with their right foot; they are more stable on the left, so it is the left leg and foot from which they make the weight transfer and drive the body up. Similarly, when people step down from a kerb, they tend to ’lead’ with their right feet because they want to be as stable as possible as they accelerate downwards, and the left leg provides the more stable platform for this dynamic balance shift. In addition, most people exhibit better co-ordination on a balance board with their left foot and leg than with their right.

Is the right leg really weaker?

If you’re not convinced, go to a track meet and watch the high jumpers. The vast majority explode upwards off the left foot, propelling the right leg up and over the bar first. Or go to a basketball game and watch closely as players make running ’dunks’; the majority of these dunk shots will be performed off the left foot.

Before we dismiss the right leg as being a weak sister to the left, however, let’s go back to our sprinting example. As I mentioned, most sprinters start a race with the right leg back; when the gun goes off, they explode forwards as the more highly-flexed left leg recoils, and they swing the right leg ahead to make first contact with the track. Some experts contend that sprint starts happen this way not because the left leg is a more powerful ’pusher’ but because the right leg is the faster one, better able to accelerate forwards to complete the first critical stride of the race. These experts tend to focus on the fact that running speed is not just a function of explosive footstrikes but also of the rate at which the ’swing’ leg is accelerated forwards. The faster you can move your swing leg, they argue, the greater will be your maximum running velocity, and it is hard to argue with this contention.

Thus, we seem to have two ’contrasting’ views: the right leg can be seen as either the quicker leg or the weaker one. However, these views are not necessarily opposing. In fact, it makes sense that if the left leg truly is more explosive when the foot is on the ground, it would accelerate the body forwards more dramatically than the right leg would, and thus there would be a greater need for enhanced ’swing’ velocity in the right leg - just to keep up with the faster-moving body!

Lateralism and your training

How relevant is all this to your training? It is very likely that you have a dominant leg and foot. If you run in your sport, it’s quite likely that footstrike is of shorter duration on one side than the other and that stride length is longer with one leg than the other. If the left leg and foot are truly stronger and more powerful than their right counterparts, you would expect footstrike time to be shorter with the left foot and stride length longer with the right. If this is true for you, you will run better if you can train your right leg to become as powerful as your left one.

How can you determine whether you have a dominant leg?

To get a general feeling for right and left leg function, ask a friend to time you with a stopwatch as you hop on your left foot for 30 metres as fast as you can - ideally on a day when you are feeling energetic and well-rested. After you have recovered, sprint-hop the same distance on your right foot, and compare the times. Make sure your friend counts the number of hops you take with each foot over your 30m course; if there is a time disparity between feet, you can then decide whether the discrepancy is due to hop length or footstrike time: if your left-hopping time is faster, for example, but the number of right and left hops are the same, you can assume that your left foot is quicker off the ground - ie more powerful - than your right.

To test for basic leg strength:

• Warm up thoroughly
• Rest a 55-65lb barbell on your shoulders and complete as many one-leg squats on your right leg as you can.
• Rest until you have recovered completely, and then repeat on the left.

Try the exercise again on another day, reversing the order - ie left then right.

Here’s a great test of running-specific strength:

• Run for 50m or so at about 10K pace along a dirt road which is just soft enough to leave your footprints on its surface.
• Then use a tape measure to measure the lengths of the strides generated by each foot. Take the average of about 10 left and 10 right strides, and compare them.

The results of this test could have some interesting implications. Let’s say that your left leg does indeed generate longer strides than your right.

This could be for two reasons:

1. The muscles in your left leg are simply stronger and so generate more force, given equal stimulation by the nervous system

or

2. The muscles in your legs have equal strength, but your nervous system does a better job of recruiting and co-ordinating your left leg muscles during the act of running, thus producing longer strides off the left foot. If the latter is true, then your asymmetry will tend to become more pronounced over time. Although your muscles currently have equal strength, the fact that the left leg muscles are producing more force 90 times per minute than those in the right leg means that the left muscles will inevitable get stronger. In either case, though, your key aim should be to help your less capable leg ’catch up’ with the dominant one. If you do this, you’ll end up with two dominant legs and will run significantly faster.

But how can you help the weaker leg to catch up?

My recommendation is this:

When you are in the special-strength phase of your training, completing lots of exercises which mimic the mechanics of running, such as:

• One-leg squats
• Runners’ poses
• Partial squats
• One-leg heel raises
• High-bench step-ups
• Bicycle leg swings
• Eccentric reaches with toes

You should aim to complete extra reps - and maybe even an extra set - with your weaker leg. Every four weeks or so, use the one-leg squat test described above to see if the asymmetry has become less marked.

When you are in the explosive portion of your overall programme, performing lots of movements which emphasise running-specific motion and high speed, make sure you do lots of extra hops, Chester bounds, one-leg hops on-the-spot, depth drops, one-leg squats with lateral hops, and high-knee explosions with your less powerful foot and leg. Test for power equality every four weeks or so by measuring the distance you can cover in 10 seconds of explosive hopping on each foot. If you’re like most athletes, your left leg and foot are probably stronger than the right ones. Right now you can probably do more heel raises, step-ups and partial squats on your left leg than your right. And - the really key point - you’re probably stronger with your left leg when you run. Fortunately, though, leg function is not etched in stone: by working on your non-dominant leg, you can improve your symmetry - and your speed!

Owen Anderson