Welcome to Pedal Science, the weekly bike fitting blog by Nick Thomas of The Endurance Coach. This week our resident bike fitter Nick Thomas talks about cleat position.
Cleat fore-aft position will affect pedaling efficiency but should special consideration be given if someone is competing at triathlon? There are several points a triathlete should consider when setting up their cleats:
- Riding style:
Road racing requires constant change of pace and efforts when attacking, climbing and exiting corners. This requires a certain amount of muscular elasticity and explosiveness which the calf muscles will assist with. Conversely triathlon (and time trialing) requires a consistent effort which deliberately avoids sudden increases in speed. The most efficient cleat fore-aft position can therefore be different for each discipline.
- Muscle fatigue:
The further forward cleats are fitted the longer the lever arm from the cleats to the heel. As ankling is achieved with muscles of the lower leg the longer the lever the greater the muscular action required to achieve the necessary ankling. Excessive muscular fatigue is something cyclists should avoid but for triathletes this is more problematic as the same muscles are required to provide propulsion when running. Excessively tired calf muscles will compromise running efficiency and result in a less propulsive gait.
It’s also worth noting that shoe choice also impacts on muscular fatigue. If the foot flattens when pressure is applied (often as the leg internally rotates) the deeper muscles which control pronation will be worked harder: this also affect running gait as the foot is consequently less effective at supinating, an essential requirement to achieve an efficient running gait. This fatigue can be experienced if using a spinning bike wearing trainers as the shoe flexibility exacerbates the problem – people will often experience more lower leg fatigue with burning in the calves and under the arch of the foot. Cramp in the arch can often follow.
- Hip and knee angle:
The further forward the cleats are fitted the closer the knee and hip angle is at the top of the pedal stroke. This can be problematic for anyone with knee problems and when there is limited flexibility in the hip. For a triathlete this is even more relevant as there will be a run to complete immediately after the bike: riding for up to 112 miles with the hips in an unnaturally flexed position will cause the hip flexors to tighten and therefore limit hip extension, something which is essential to achieve an effective, propulsive running gait.
So where should a triathlete position the cleats? A cyclist should usually set their cleats up so the pedal spindle is around 1cm behind the metatarsophalangeal joint (the prominent joint on the medial side of the ball of the foot). For a triathlete we suggest this position is moved more posteriorly so the lever arm is shorter.
A triathlete will be fatigued at the start of the run regardless of cleat position. However the fatigue should be reduced as much as possible by minimising unnecessary muscular work during the bike. By choosing an appropriate shoe combined with a more logical cleat position gait will be more efficient and run times will be faster.
Nick Thomas is the resident bike fitter at The Endurance Coach. He is a fully qualified bike fitter and expert in lower limb mechanics, holding a BSc (Hons) in podiatry. You can contact him using the email address: firstname.lastname@example.org or see more about his fitting services by GOING HERE