2 The 109% method

A more robust method was developed by Hamley & Thomas in a 1967 paper. They experimented with different saddle heights and found that the ideal was achieved when the saddle was positioned at 109% of your inseam length when measuring from the pedal axle to the top of the seat height. 

Your inseam measurement is basically the length from your crotch to the floor. To calculate this, face a wall and put a thick-ish book between your legs as if it were a saddle. Ensuring that you are standing straight with your heels on the floor, mark a line along the top of the book edge touching the wall. 

The distance from the floor to the height of the mark is your inseam measurement. It’s best to measure it several times and take an average. 

This has proved an extremely popular method and is recommended by many top-level coaches. Yet a recent study by Professor Pelever found that it was inferior to the Holmes method (see below) both in terms of power output and economy.

3 The LeMond method

This is a popular variation on the 109% method and pioneered by the three time Tour de France winner Greg LeMond.

Also using inseam length as a guide, this formula calculates 88.3% of your inseam length and uses it to measure the distance from the centre of the bottom bracket to the top of the seat height.

Interestingly, Pelever has shown that this often produces a different seat height from the 109% method and although it seems to work for many people, it may not be ideal for someone with particularly long femur bones.

This was originally developed to reduce over-use injuries in cycling and takes a different approach entirely from the other three. 

It uses a device called a goniometer for measuring the angle of the knee joint at the bottom of the pedal stroke. Holmes recommends an angle of between 25 and 35 degrees and closer to 25 for those with a history of patella tendonitis.

This may all sound a bit technical and if so it’s probably best to go with one of the two inseam methods, but you can pick up a goniometer for around £20 from medical suppliers.

Pelever’s research has shown that setting your seat height based on a knee angle of 25 degrees outperforms all other methods (including an angle of 35 degrees). “Using a goniometer and a 25 degree angle is definitely the method I’d recommend,” he says.

Don’t rely on simply feeling comfortable either. “If you’ve been pedalling at a much lower saddle height than is optimal, it may feel awkward in the beginning,” says Pelever. 

“However, as your body adapts (usually in two to three weeks) the new position will not only feel comfortable, but will improve performance in the long run.”

Of course, if you still feel uncomfortable after a few weeks then you will need to make changes. It’s best to use the 25 degree knee angle as a starting place. Have someone watch from behind to ensure that your hips do not rock back and forth across the saddle due to over extension at the bottom of the stroke. If that is the case then the angle may need to be adjusted upwards slightly for comfort.

“When I finish fitting someone on their bike, their knee angle is usually somewhere between 25 and 30 degrees, but much closer to 25 on most all occasions,” says Pelever.