Bike Right, Bike Fit

August 24, 2016 by Liz

by Meryle Richman, PT, DPT, MS, CST, RYT

With the beginning of fall and changing of the leaves, people enjoy being outdoors riding their bicycles. The physical therapists at Ivyrehab can teach you preventative measures to avoid bike injuries.

For the average bike rider cycling involves a limited repetitive motion. At an average cadence of 90 revolutions per minute (RPM), a bicycle rider cranks out 5,400 strokes each hour. This becomes 1.5 million strokes in 5,000 miles. So you can just imagine how this can lead to a lot of wear and tear on the cartilage, ligaments and joints of the knee.

I. What you need to know about for a proper Bike Fitting:

The most common bike fitting errors include a saddle that is too high or too low, excessive handlebar reach that causes you to lean too far forward, and improper alignment of the pedal and shoe.

The American Physical Therapy Association recommends that when evaluating a cyclist for a proper bike fit the following assessment be performed:

●Foot to Pedal: The ball of the foot should be over the pedal spindle (the bar in the middle of the pedal on which the pedal “spins”). For cleat users, it is important to establish a neutral position of the cleat on the shoe. This will allow for neutral tracking of the knee through the pedal stroke.

●Saddle and Knee/Pedal Position: Saddle height should allow the knee to be slightly bent at the most extended portion of the pedal stroke. A suggested knee angle at dead-bottom-center is 30- 35 degrees while the foot is in the pedaling position.

●Saddle tilt: Saddle tilt for normal-endurance bicycling should be level. Pay close attention to the portion of the saddle that will be supporting the ischial tuberosities, or “sitting bones.” Cut out saddles allow for better tissue oxygenation. A well-fit saddle will provide the best comfort and results.

●Saddle Position in relation to the handlebars: Saddle position should allow the knee to be over the foot (metatarsal heads, ball of foot) at the 3-o’clock position of the bicycle crank-arm. The foot should be in a normal pedaling position.

●Handlebars: The position of the handlebars will affect the comfort of the hands, shoulders, neck and back, as well as the overall handling of the bicycle. For the Recreational Rider the trunk angle (trunk from horizontal reference line) should be angled between 40-80 degrees, and the shoulder angle (trunk to humerus) should be between 80 and 90 degrees. The handlebar position, should allow the hands to be slightly wider than the shoulder width. This is for comfort of the hands, arms and shoulders. For the Road Rider the trunk angle (trunk from horizontal reference) should be between 30 and 40 degrees, and the shoulder angle (trunk to humerus) should be between 90 and 100 degrees. The handlebar position should be approximately 2 centimeters (or .79 inches) wider than shoulder width for comfort of the hands, arms and shoulders.

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The ideal position of the knee in pedaling is to have the knee over the pedal and ball of the foot at the 3 o’clock position.

II. Common Overuse Injuries with Biking

● liotibial Band Syndrome (IT Band):

Possible causes are too-high saddle, leg length difference, and misaligned bicycle cleat for those who use clipless pedals. Pain is caused when the band becomes tight and rubs over the bony prominences of the hip (greater trochanter) and/or the knee (lateral epicondyle). When the knee is flexed at 30 degrees and is at the bottom of the stroke motion, there is friction on the tendon attachment. Tight inflexible lower extremity muscles may also worsen the condition. The band becomes tight and pulls at the hip and knee causing pain. In order to minimize knee and hip pain, it is important to pedal with low resistance and keep the cadence at 80-90 rpm.

● Chondromalacia:
Another common knee injury is anterior knee pain, such as chondromalacia. This involves irritation of the cartilage behind the patellar and patellar femoral tracking of the knee. If there is a muscle imbalance of the muscles of the anterior thigh known as the quadriceps, the outside muscle (vastus lateralis obliqus) becomes tight and the muscle on the inside of the thigh (vastus medialis obliqus) becomes weak. This results in lateral movement of the patellar which does not “track” smoothly in the patellar groove and results in irritation to the patellar (patellar-femoral maltracking) and anterior knee pain.

● Hamstring Tendinitis
Possible causes are inflexible hamstrings, high saddle, misaligned bicycle cleat for those who use clipless pedals, and poor hamstring strength.
● Neck Pain
Possible causes include poor handlebar or saddle position. A poorly placed handlebar might be too low, at too great a reach, or at too short a reach. A saddle with excessive downward tilt can be a source of neck pain.
● Lower Back Pain
Possible causes include inflexible hamstrings, low cadence, using your quadriceps muscles too much in pedaling, poor back strength, and too-long or too-low handlebars.
● Hand Numbness or Pain
Possible causes are short-reach handlebars, poorly placed brake levers, and a downward tilt of the saddle.
●Numbness or Pain
Possible causes are using quadriceps muscles too much in pedaling, low cadence, faulty foot mechanics, and misaligned bicycle cleat for those who use clipless pedals.

III. Prevention of Injuries with Stretching & Exercising

●Warm up for 5 – 10 minutes with gentle movement. Stretch slowly and gradually. Also do some stretching after you ride
●Exhale as you gently stretch muscles. .Develop a stretching routine for the quadriceps, hamstrings, ilio-tibial band, piriformis and calves Also, do stretching for your neck, trunk, chest, wrists and hands.

●Hold stretches for 15 – 20 seconds; 2 – 3 repetitions

●Gradual resistive exercise for back musculature, abdominals, legs and arms

●Progress to closed chain exercises

●Progressive functional activities and agility skills

●Partial squats, step – ups and step – downs, lunges

●Proprioceptive training – balancing exercises

●Cross training: spinning, jogging, swimming

IV. Choosing a Correct Helmet

When you are choosing a helmet, fit is very important. For a helmet to protect you it must fit correctly. Other factors to know about a proper hat fit are:

●Make sure the helmet fits on the top of your head and does not tip backwards or forwards. It should be parallel to the ground. There should be about 2 fingers breadth between your eyebrow and the edge of the helmet
●The helmet should not move when you shake or move your head from side to side or up and down.
●Straps should always be fastened and fit snugly. It should also meet certain safety criteria. Look for “Snell Certified” or Meets ANSI Z904 Standard” on the box or on the helmet itself.
●There should be no cracks inside the helmet

Whether you are a beginning bicyclist or advanced rider and have and have an injury that is “holding you back from riding” our experienced and dedicated licensed physical therapists can help you get started. With Direct Access a prescription is not required to be evaluated. Contact Ivyrehab Briarcliff (914) 762 – 2222 and Ivyrehab Jefferson Valley (914) 245 – 8807 or visit our Website: www.ivyrehab.com to learn more about Direct Access.

Reference: www.apta.com

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