LOW BACK PAIN IN CYCLISTS
more than just set up
Some have called cycling “the new golf” with an explosion of “MAMIL’s” or Middle Aged Men in Lycra. some carrying it off better than others!. That aside, what ever the reasons for cycling, be it for fitness, pleasure or competition, being comfortable on the bike not only maximises enjoyment, but improves power output. Studies have suggested that the incidence of back pain in cycling, may be as high as 70%. With this staggering statistic, it’s important to eliminate any factors that may contribute to low back discomfort especially if you have some goals with your riding. Most people understand the importance of a correct cycle set up but there are other factors that can cause low back pain in cycling.
Keeping the pelvis still on the saddle ensures the legs have a stable platform to push from and minimises excessive movement of the lumbo-sacral spine. Considering that the cranks are turned over an average of 4500 x per hour, there is fair potential to cause problems if things aren’t right. The factors that place load on the lower back include:
- Pedalling technique
- Saddle height
- Saddle tilt
- Muscular endurance
Pedalling in circles is not as simple as it may seem. There are some key components to focus on during each part of the revolution. The power phase of the pedal stroke is between 12 o’clock and 6 o’clock. Different muscle groups will activate strongest at varying times during the stroke but all have their part to play. Things to focus on are as your come over the top of the stroke , your toes should be slightly pointed down, pushing your knee forward in preparation for the down stroke. From the 1o’clock position, focus moves to the downward drive and getting the heel down to approximately 20 degrees at the 3 o’clock position. The calf muscles activate greatest at the 4 -7 o’clock range to “scoop the bottom of the pedal stroke”
The up phase of the pedal stroke is not totally passive but unless you’re in the throes of an attack or your last big effort, then pulling up is an inefficient use of muscle activity. Most important is the alignment of your hips, knees and feet. From the front, these should all align over the centre of your foot with the mental cue of your “legs as pistons”
A study performed on cyclists has demonstrated that riders with a greater degree of lower back flexion or curvature had a higher incidence of low back pain. Whether this was resulting from poor flexibility, postural habits or incorrect setup was not clear. It did however support the fact that if you sit with a greater degree of bend in your lower back, there was a strong correlation with the development of low back pain. This is especially relevant for Triathletes and those specialising in Time Trialing where aerodynamics is such an important factor. There is a point where free speed from positioning yourself more aggressively could be completely negated if you’re too uncomfortable. As a general guideline, I recommend athletes who compete in longer races such as Ironman, should focus on comfort first unless they are very experienced and have refined their position over a long period of time. Kinematic analysis can identify those riders who sit with a greater degree of lumbar flexion and who require position modification.
Much time and research has been dedicated to what constitutes the optimum saddle height. One formula established at the Australian Institute of Sport demonstrated the greatest power outputs when the saddle was within 96-98% of Trochanteric height. More experienced riders favoured ranges higher in that range as did time trial and triathlon specialists. Saddle height will influence lower back posture hence it’s relevance with low back pain. Saddle heights that are too high encourage reaching at the bottom of the stroke which in turn causes the pelvis to rock side to side. Observation of riders from behind can identify excessive lateral movement. Correct saddle height and drills that focus on stability can help correct this pattern of movement.
One study conducted on the effects of saddle tilt on lower back pain suggested that altering the angle of saddle will influence the pressures placed upon the lower back. Their findings suggested that tipping the front of the saddle upwards by 10-15o may reduce pressure and subsequently pain in the lower back. Practically this may be uncomfortable and place undue pressure on other areas. Alternatively making postural adjustments in the saddle may achieve a similar reduction in forces. This may be dependant on correct muscle balance and adapting new motor patterns or postures.
One of the determinants to adopting good cycling posture is flexibility of key areas. This is most relevant when time trialing or with triathlon bike set up. To improve aerodynamics, one way is to reduce frontal area by getting lower and effectively smaller. Forcing the spine into a position that is not comfortable due to lack of flexibility will eventually result in pain and subsequent drop in performance. The key area’s of flexibility for cyclists are the hamstrings, gluteals, lower back extensors and the hip flexors. Ensuring good length of these areas reduces tensile and compressive forces around the lower back and pelvis. Simple muscle length testing can identify tightness with appropriate prescription of stretches.
The lower back muscles play an important role in stabilising the pelvis on the saddle. They work hard in an isometric fashion (without movement). Like any new exercise or one where you are increasing either intensity or duration, muscles need to make adaptive changes in response to the new load. During that conditioning phase, muscles get sore but when they recover, they get stronger. Higher intensity efforts will amplify the work load such as climbing in the saddle or flat road, large gear work.
Cycling can involve many hours of riding especially if you have goals to complete a long distance event such as Round Lake Taupo. Clearing all contributing factors to back pain will lead to a much more pleasant experience and better outcomes. Consider all these factors or consult your local experts to help eliminate back pain from your riding experience.
Craig Neale is a Physiotherapist based in Hobsonville, Auckland. He has previously worked with Cycling NZ, the Auckland Branch Sports Medicine NZ and currently competes in Triathlon
 Br J Sports Med 1999;33:398–400 Efect of changing the saddle angle on the incidence of low back pain in recreational cyclist, Moshe Salai, Tamar Brosh, Alexander Blankstein, Arial Oran, Aharon Chechik
 Abstracts from the IOC World Conference on Prevention of Injury & Illness in Sport, Monaco 2014 LOW BACK PAIN IN CYCLING: DOES IT MATTER HOW YOU SIT?
 Br J Sports Med 1999;33:398–400,Effect of changing the saddle angle on the incidence of low back pain in recreational bicyclists, Moshe Salai, Tamar Brosh, Alexander Blankstein, Arial Oran, Aharon Chechik