Setting the correct height of the seat is the basic thing on the bike. One thing on which all experts agree is that if the height is set wrong, the consequences can be disastrous. The study proves that setting the seat at too low height can increase your exhaustion to 12%.
The heel method
Place the heel of your shoe on the pedal and set the seat height so that the entire length of the feet from the pedal to the seat is set straight while sitting on the bike. Despite the fact that this method is often used, there is no scientific evidence to support it and can often lead to setting the seat height too low.
It is a method that has been developed and is described by the duo Hamley and Thomas. They experimented with seats of different heights and found that the saddle is ideally placed when it is raised to 109% of crotch length when measured from the pedal axle to the top of the seat height.
Crotch length is basically the length from your crotch to the floor. To measure it, stand facing the wall and put a book between legs at the place where would normally saddle be placed, when you sit on it. Make sure you stand straight with your feet on the floor and mark a line on the top cover of the book in a place where touching the wall.
Distance from the floor to the marked place is your crotch length. It is best to measure several times and takes into consideration the mean value.
This method also, uses crotch length as a guide, and calculates 88.3% of your crotch length and is used to measure the distance from the center of the bottom bracket to the top of the saddle height.
It was originally developed to reduce excessive injuries in cycling, and has a different approach than the previous three. It uses a device called goniometry to measure the angle of the knee and the bottom of the pedal. Holmes recommended angle of 25 and 35 degrees, and closer to 25 degrees for those with a knee injury. Goniometry can be purchased in stores specialized for medical equipment.
This method might sound a bit technically demanding, and if they are, you can always use the methods from above. Even thought it might sound a bit demanding, the method is the most effective.
It is best to use 25% as a starting point measurement. Let someone observe you from the rear and monitor that your hips do not go back and forth across the saddle. If this is the case, then you need to adjust the angle slightly.