Phil Mosley explains simple ways to help you run faster at your next triathlon.

Let’s face it, nobody enters triathlons because they’re easy. We all accept it’s a tough sport and that aching legs are to be expected. At the same time if your legs get too sore during a race it’ll reduce you to a shuffle when you should be running strongly to the finish line. So how can you avoid this happening to you? Here are three tricks to help reduce heavy legs and muscle pains, so you can swim, bike and run faster and in greater comfort.


Are you an over-kicker?

If you have a strong and propulsive kickvwhen you swim it could be that you’re anover-kicker. This is a common stroke issue that is characterised not only by a very dominant leg kick but a poor upper body technique. The reason it’s a problem is because kicking is a relatively inefficient method of propulsion for endurance events such as triathlon. It’s so inefficient, these types of swimmers are often very short of breath while swimming.

Over-kickers typically have a good body position in the water, but this is achieved through a strong and energy sapping kick rather than through good balance in the water. Over-kickers tend to struggle when swimming with a pull buoy and often feel unbalanced when wearing a wetsuit. Their body rotation is generally poor and they swim relatively flat in the water. As triathletes, over-kickers often complain of tired legs on the bike and run.

Areas to work on:

  • Focus your propulsion to your upper body, rather than your legs. This requires a leap of faith on the part of the swimmer – it takes confidence to let go of your precious leg kick and still know that you’ll swim well.
  • Making this shift makes swimming feel like hard work and may result in muscle fatigue in the back, chest and arms initially. Don’t worry, this will improve over time.
  • It’s essential to improve your body roll in conjunction with a good arm-catch and feel. This often requires a longer stroke and a slightly slower stroke rate.

Best drills for over-kickers:

Put a pull buoy between your thighs and perform 15 metres of sculling. This is a simple but effective drill at the front of your stroke, where you circle your hands, in a high elbow position. You should feel a light pressure on the palms of your hands.

Then after 15 metres, start doing normal full stroke swimming – still with the pull buoy – feeling that pressure on the palms of your hands and focusing on pressing it backwards to the wall behind you.

Then after 20 metres of this, release the pull buoy and carry on swimming as you were when you had the pull buoy – focusing on the light pressure on the palms of your hands. Of course, you will need to kick slightly without the pull buoy but keep the focus on your arm-led propulsion.


Do you have the right gears?

The key to saving your legs on the bike is to ride at a constant effort throughout your race, avoiding big fluctuations in intensity or power. That’s simple enough on a flat course, but it can be very challenging on hilly routes or in strong winds where you are forced to ride hard at times. The key is to choose the right gearing for each event. For hilly routes, you need a range of easy gears so you can tackle ascents without blowing your legs to smithereens. If you ride with gears that are too big it forces you to maintain a high power output at a low cadence (revs per minute) every time you hit an ascent. These constant spikes in power cause a build up of lactic acid in your legs that eventually lead to muscle micro-trauma. You see it all the time at hilly triathlons – people pushing gears that are far too big and needlessly making their legs sore.

The range of gears you have on your bike is determined by the cassette and chainset. Here’s how to pick the right ones for your ability and goal-event.

How to choose the right cassette:

The cassette is the cluster of sprockets situated on the hub of your rear bike wheel. Cassettes provide you with a range of gearing options for your chain to use. A good range of gears on your cassette allows you to always choose the optimal gear so that you can keep pedalling smoothly. The main thing to consider is the spread of gears on the cassette. Each sprocket on your cassette has a certain number of teeth, with bigger sprockets having more teeth. The smaller the difference between your biggest and smallest sprockets, the smaller the jump between gears; allowing for a smoother gear change. However, for tough, hilly routes you may actually need a wide spread of gears.

Here is a general guide to choosing a cassette – but ultimately it depends on how strong a cyclist you are. Stronger cyclists can handle bigger gears at their optimum cadence, and vice versa. The numbers refer to the number of teeth on the smallest and
biggest sprockets of the cassette:

  • For flat or gently rolling courses, choose an 11-26 cassette.
  • For undulating to hilly courses, choose an 11-28 cassette.
  • For very hilly courses choose an 11-32 cassette.

How to choose the right chainset:

The chainset is the group of components that rotate when you turn your pedals. On most triathlon bikes the chainset has two chainrings. The number of teeth on each ring affects your gearing. You can get two types of 2-ring chainsets. A ‘standard’ chainset typically has a 39-tooth inner ring – this is ideal for flat or gently rolling routes. If you want easier gears, you can also get a ‘compact’ model which has a 34-tooth inner chainring which effectively gives you lower gears to help when climbing, or ‘semi-compact’, which has 36.

How gearing effects your legs:

To give you some idea of how your choice of cassette and chain-set effects your legs, check out these different gear ratios. The numbers refer to the teeth on the smallest ring of your chainset and the biggest sprocket of your cassette.

Let’s imagine that your easiest gear is currently a 39×25…

• A 39×27 would be 9.7 per cent easier.
• A 39×28 would be 12.9 per cent easier.
• A 39×32 would be 22.6 per cent easier.

This would give you the option of pedalling faster up hills (known as a higher cadence) for the same power output. Or you could choose to pedal at a lower power output for the same cadence, sacrificing a little speed. Both of these options might help save your legs for the run.


Are you an over-strider?

Avoiding over-striding is a great way to preserve your legs during the run. Generally when people run with a longer stride it increases the load on their knees and hips. A longer stride also tends to be associated with greater up and down movement, which requires more effort from your legs to cushion your fall each time.

By shortening your stride it can reduce the amount of work that your knee and hip have to do while you run. This can lead to reduced soreness and faster run splits.

How to tell if you’re over-striding:

1. Measure your cadence using a smart phone app such as CadenceTrainer (99p, App Store) or a metronome such as the Finis Tempo Trainer Pro (, £31.99). If it’s down near 150 to 160 steps per minute there’s a pretty good chance you’re over-striding. It’s normal to increase your stride rate when you’re running at top speed – so aim to do this exercise at your normal training pace.
2. Ask a friend to film you running at a track, then watch the video in slow motion to see if your ankle lands far in front of your knee.

Five ways to avoid over-striding:

  1. Increase your cadence. Aim to run at 170–190 steps per minute. Falling outside of this isn’t necessarily bad, but can indicate under or over-striding.
  2. Minimise ground contact. Imagine you’re running on water. To avoid sinking, you need to tap the surface lightly and quickly. The less time you spend in contact with the ground, the more efficiently you run.
  3. Generate forwards movement. Imagine you’re running on an un-motorised treadmill. In order to keep running you need to pull the treadmill belt backwards with your feet.
  4. Avoid the wall. Imagine running on a treadmill with a wall just inches in front of your nose. If you try to stride too far ahead of your body your knee or foot will hit the wall. To avoid that, drop your feet directly under your hips.
  5. Avoid the ceiling. Imagine you’re running beneath a ceiling that is just two inches above your head. To avoid banging your head you’ll need to minimise the up and down.


First published in Triathlon Plus Magazine, Issue 98

Pictures: Shutterstock

Cover Picture: Evergreen