Team Triathlon Plus take their team carbon bikes for a professional bike fit with Retul specialist Andy Sexton.

Team Triathlon PlusIt doesn’t matter what type of bike you ride or how much it cost – if you aren’t in biomechanical harmony with it, you risk injury and reduced performance. A professional bike fit should therefore be at the top of every triathlete’s priority list. So in a bid to avoid any disasters before the Virgin Active London Triathlon, we sent off our in-house dream team with their custom Team Carbon bikes to see Ironman veteran Andy Sexton at Bike Science ( in Bristol.

  • The Retül low-down

Sexton was one of the first fitters in the UK to become Retül certified and has fitted more than 500 riders in the past five years. The system is unusual in that it’s designed to work out how a rider fits on their bike when pedalling, rather than when stationary. Launched in 2007, it uses an infrared camera to give instant 3D feedback on riding biomechanics by tracking body position and pedalling movement.

It does this via a collection of LEDs placed on your joints – the camera records their position 29 times per second and this data, combined with the fitter’s expertise, forms the basis for adjustment. The end goal is the ‘perfect position’ – something that’s different for every rider. A full ‘Level 2’ fit takes at least two-and-a-half hours.

  • Strength and flexibility

The first step of the fitting process is a strength and flexibility test. If you’re as stiff as a poker, like team member Rich Sage, the fitter won’t put you into a super-efficient, super-aerodynamic position on the bike because you won’t be able to sustain it. But don’t despair – daily stretching and strengthening exercises can sort out even the least flexible riders, who can then return to tweak their position.
“To cycle efficiently, you need a good range of motion in the hips and lower back, as well as a stable and well aligned base (pelvis),” says Sexton. “If one of these areas is lacking, your body will compensate by recruiting other muscles to achieve the power required to push the pedals around. Not only does this reduce performance, the change in posture also hikes up your injury risk.”

  • Posture

Bad posture is as common on the bike as it is off and the results are just as painful and debilitating. “When riding a bike, the back should be arched, with no noticeable changes in the curvature of the spine,” says Sexton. “However, not everyone can achieve this ideal position due to individual strength and flexibility limitations. Most riders have some sort of asymmetry. The skill in fitting is to decide on the best compromise to allow for these asymmetries.”
Sexton focuses on three areas: cleats, seat and handlebars. Every change he makes to the bike has a knock-on effect. For example, raising the saddle increases the reach and the drop to the bars, while moving the cleats affects leg extension and saddle height.

  • Road bike vs TT bike

The unique geometry of a TT bike means a rider can achieve a more aggressive and aerodynamic position than on a road bike, but Sexton says the principles of posture remain the same. “It doesn’t matter what type of bike you ride,” he explains. “The aim is always to ensure that the skeleton is structurally supporting the body, rather than the muscles. An overstretched position causes fatigue, loss of power and possible injury.”

  • Pedalling forward

Forget lightweight wheels and carbon pedals – the simplest and most effective way to improve your performance is to invest in a bike fit. Granted, a new position isn’t going to transform you into Bradley Wiggins overnight, but the small investment (prices for a Retül Level 2 fit start at £150) should pave the way for years of pain-free and efficient cycling. is the online home of Triathlon Plus – the best source of triathlon training advice, triathlon gear reviews and triathlon news.

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