Measuring Your Body for Road-Cycling
Accurate body measurements are the foundation of selecting a road bike and achieving a proper bike fit. Aligning your bike’s geometry with your body dimensions ensures maximum comfort and efficiency while reducing the risk of injuries. Key measurements include your inner leg length, torso length, arm length, shoulder width, and foot dimensions. These measurements influence saddle height, handlebar reach, frame size, and cleat positioning.
If you are experiencing pain or discomfort on the bike, want to improve performance, or are planning to invest in a new bike, we always recommend a professional bike fit. These are invaluable for accurately measuring your body and providing tailored recommendations. They are about enhancing your cycling experience, not upselling.
There are also many apps and online services to help you understand your dimensions, flexibility, and posture.
a. Height
Your height serves as the baseline measurement for choosing the correct bike size and frame geometry.
How to Measure
Stand barefoot against a wall with your feet together and your back straight. Place a book or flat object horizontally on your head, gently pressing it against the wall. Mark the spot where the bottom edge of the book meets the wall, and measure from the floor to this point.
Practical Tip
If measuring alone, use a mirror to ensure the book is level, or record a video to double-check your alignment.
b. Inseam
Inseam (inner leg) length determines your saddle height, crank arm length, and stand-over clearance.
How to Measure
Stand barefoot against a wall, place a book between your legs to simulate saddle contact, and measure from the floor to the top edge of the book. This is your inner leg length.
Practical Tip
Measure both legs and take the average.
Traditionally, the LeMond method to calculate saddle-height (center of bottom bracket to top of saddle) is Inseam × 0.883. However, due to wide variation in bike-geometry, crankarm length and different performance objectives, this isn’t always best today. We have a section about setting up your saddle in our Bike Fitting Chapter.
Expected Ratio
The inseam is generally 45–47% of your total height, though this varies based on leg proportions.
c. Torso Length
Torso length helps determine your bike’s top tube length and handlebar reach.
How to Measure
Measure from the base of your neck (where your collarbone meets) to your waistline.
Practical Tip
Use a bike-fitting calculator to input your torso and arm lengths to determine your ideal reach and recommend top tube length. This ensures a correct riding position without overstretching, though cycling style should also be considered.
Expected Ratio
Torso length is typically 32–35% of your height, but the ratio depends on your body type.
d. Arm Length
Arm length influences your handlebar reach and stem length.
How to Measure
Measure from the shoulder joint to the centre of your palm with your arm extended horizontally.
Practical Tip
Most brake levers are adjustable for resting angle to accommodate different reach and hand sizes. Consult the manufacturer's instructions or search online for guidance.
Expected Ratio
Arm length is generally 38–40% of your height, but individual proportions vary.
e. Shoulder Width
Shoulder width determines the appropriate handlebar width, improving control, balance, and comfort.
How to Measure
Measure the distance between the bony protrusions on your shoulders.
Practical Tip
Handlebar width traditionally matches your shoulder width. However, with more handlebar types available nowadays, this is not always the case. Wider handlebars offer more stability, while narrower ones improve aerodynamics.
Expected Ratio
Shoulder width is typically 20–25% of your height.
f. Feet
Foot dimensions affect your cycling shoes and cleat setup and may also influence crank-arm length.
How to Measure
Measure the length and width of both feet, as well as the distance from the tips of your toes to the ball of each foot to aid cleat positioning.
Practical Tip
Wear the same socks that you do for cycling.
Selecting an appropriate shoe width is crucial to minimise leg twisting and injuries. Custom insoles or arch supports add comfort and reduce left/right imbalances between legs. Proper cleat positioning enhances power transfer and reduces discomfort; when in doubt, a lower position is often better.
Expected Ratio
Foot length is typically 15–17% of your height, but variations are common.
g. Sit Bone Width
The width of your sit bones (ischial tuberosities) is one of the most important factors for comfort in road cycling, as it dictates the saddle that should fit you.
How to Measure
Place a piece of carboard of a firm surface (such as a cofee-table.) Sit firmly ontop of the cardboard with your weight evenly distributed. Stand up and check the indentations left by your sit bones, which should be distiguishable. Mark the center of the bones and measure the distance between the centres using a ruler or tape measure in millimetres.
Practical Tip
Width is important but not the only factor when selecting a saddle. Bike fitters often use specialist tools to measure sit bone width and heat map seats to analyse your sitting position. Experiment with different saddles, but remember that saddles are designed for your sit bones to be on the wider rear section.
Expected Ratio
Sit bone width typically range from 110–140 mm, and you should normally add 20-30mm to get your ideal saddle width.
h. Hamstring Flexibility
Hamstring flexibility is important when trying more aggressive cycling styles that require extended amounts of movement in hunched positions.
How to Measure
Sit on the floor with legs straight and reach for your toes, holding for 5secs.
Practical Tip
Stretch well after a cycle to help improve flexibility over time.
Expected Ratio
If you cannot reach your toes, you need to improve your hamstring flexibility before adopting aggressive styles. If you can touch your toes, that’s good, and being able to comfortably hold your toes is elite, although may depend on your arm-to-leg ratio.
i. Core Strength
Core strength is important for all styles of cycling, particularly for longer rides. Being able to keep your back straight, shoulders back and lungs open aids breathing and stamina. Core strength is also essential for balance, control, and handling.
How to Measure
Time yourself holding a plank on floor. I.e. lie-flat with only forearms and toes on floor, holding rest of body straight and tight, with neck up.
Practical Tip
Again, this is something that can improve over time. Many excercises can improve, such as crunches, squats, ab presses, quadrupeds or planks (different versions possible). Remember to also work on back as well as abs – it’s not all about a six-pack.
Expected Ratio
You should aim to hold a plank for at least 30secs, with more advanced cyclists being able to hold for at least 2mins.
j. Neck Mobility
Neck mobility is important to road-cycling for vision. You need to be able to turn your head and see cars around you. Although you can use your shoulders to enhance a twist, this can lead to injury or unbalance at high-speeds. For more aggressive styles, you need to keep your head up for long periods of time and be able to twist easily in this position.
How to Measure
Sit in a chair and mimick the movements needed to look around while riding. Slowly extend neck fully back, then compress so that chin is on chest. Twist your head slowly in both directions when in extended and rest position.
Practical Tip
If mobility is low, there are mirrors you can get. End-cap mirrors or rear-view mirrors are cheap and often benefinicial for people with limited neck mobilbity. They can be distracting though, and you must be careful not to focus too much on them, keeping your eyes mainly on road in front. There are now also many rear-lights that have radar sensors. In combination with a GPS headunit, they give you information about cars approaching behind you.
Expected Ratio
You should be able to fully extend and compress your neck, with atleast 60° of rotation left and right. An aggressive cyclists should be able to rotate nearly 90° left and right.
Continue reading with Road-Bike Frame Types