The optimum sitting position

How do you sit correctly when cycling for sport? All experts agree on one point: the best position is one that is as stretched out as possible. It is easy on the back and makes pedalling more efficient. Sounds paradoxical, but it's not. A stretched sitting position brings the back into the physiologically correct, straight posture and relieves the two most important stress zones: The lumbar vertebrae and neck. The fact that this also improves aerodynamics is a positive side effect.

Slamming the saddle all the way back and preferably the cleats as well - that's old racing wisdom, and it's wrong." Robert Lechner, 1988 Olympic bronze medallist in the 1,000-metre time trial and now trainer at the European Bike Academy on Lake Chiemsee, has clear words on the subject of riding position. At the TOUR training camp in Sicily, the expert examined the posture of around 40 participants and realised that many of them were not sitting optimally on their road bikes. There was certainly a great deal of interest in the correct position.

So how do you sit correctly when cycling for sport? All experts agree on one point: the best position is one that is as stretched out as possible. It is easy on the back and makes pedalling more efficient. Sounds paradoxical, but it's not. A stretched sitting position brings the back into the physiologically correct, straight posture and relieves the two most important stress zones: The lumbar vertebrae and neck. The fact that this also improves aerodynamics is a positive side effect.

STRETCH, DO NOT HUNCH
To avoid a hunched back, tilt your pelvis forwards while sitting on the saddle. This immediately increases your reach and creates a more active, stable posture on the bike. The longer the seat length, the easier it is to adopt this position, because a hunched back simply doesn't allow you to reach the handlebars, which are far forward. The experts at Cyclefit, for example, who offer a measurement system for bike dealers and have already measured tens of thousands of athletes, build their positioning system around the "stretched seat".

This position is not necessarily comfortable at first. To actively improve your position, you have to "work on your body and not your bike", emphasises Robert Lechner. It is not the shorter stem that leads to happiness on wheels, but a stronger body. In order to keep the pelvis in the forward-rotated position for a long time, you need trained abdominal and back muscles - typical weak points of cyclists who like to devote a lot of time to their legs but neglect their torso. TOUR test rider Matthias Allwang reports with shining eyes how much better he feels on the bike after a few months of regular visits to the gym: "I've never felt so good on the bike, a whole new riding experience!"

In addition to strength training, it is also important to regularly stretch the affected muscle groups. In particular, the abdominal and chest muscles, the hip flexors, the neck muscles and the large leg muscles are shortened by pedalling. Robert Lechner has identified too short a seat length as the most common mistake in the riding position: "Very few cyclists have ever done any stretching". This needs to be counteracted - stretching should be a regular part of training. A little motivational aid: Improving your average by a few tenths is much easier with greater flexibility and a better position than simply by riding more kilometres on the bike.

THE SADDLE AS THE CENTRE
The position change on the bike must always be orientated to the athlete's current ability to stretch. The handlebars must remain within reach, and not just on the top bar. If you never reach into the lower handlebars, you are definitely in the wrong position. It is advisable to adjust the position gradually. Just like trying out other positions, this often fails in practice due to the non-adjustable stem. More on this later. Although the pre-rotated pelvis is good for the back, it is unfortunately not particularly conducive to sitting comfort, as pressure is redistributed from the robust sit bones to the more sensitive perineal area. This makes the saddle more important. You should therefore favour models that distribute the pressure well in the perineal area.

Women suffer more from sitting problems than men because the flatter slope of the pubic bone means that they have hard contact with the saddle nose even with a lower back angle. This is why women usually keep their pelvis more upright on the saddle, which limits their forward reach. Alternatively, they lower the saddle nose. This is counterproductive as you slide forwards on an inclined saddle and have to support yourself with your arms. The arms are then often pushed through to take the load, which leads to problems in the shoulder and neck area. Aerobike riders, who have to do much less muscular holding work lying on the handlebars, can lower the saddle nose a little more. Even more than for men, the advice for women is to find a suitable saddle before replacing the whole bike.

THOSE WHO DO THE MATHS ARE RIGHT
If you want to determine your optimum riding position, you should first measure your inside leg, torso and arm length. You can find out how to do this and how to calculate the correct dimensions on the bike in the PDF download "The optimum riding position" (at the end of the article) or as an Excel download from TOUR partner 2PEAK www.2peak.com/2peak/sitzposition.xls

The correct seat height can be calculated from the inside leg length and the seat length from the torso and arm length. In the sportiest position, the back forms a 45-degree angle with the vertical in the stretched upper handlebar position. In the touring position, you sit around three degrees more upright. It is important that you can reach the handlebars, including the lower handlebars. $image_right_2 If these are out of reach, something is wrong. And if you want to sit completely upright, you have to accept that the road bike is the wrong sports equipment for this. A trekking bike is then the better choice.

The correct sitting position also includes the correct cant, i.e. the difference in height between the saddle and handlebars: the handlebars should not be too far below saddle level, as the low position tends to favour a rounded back. Instead, choose a slightly longer stem. This also leads to a stretched posture; the back angle can even be the same in both cases. Therefore, always adjust the seat length first and then lower the handlebars later. If you have to stretch your arms to sit comfortably, you are sitting too long. The arms should always be slightly bent in order to absorb road bumps. In the lowest sitting position, the upper arms should form a right angle with the back. If the angle is greater, the shoulders and neck are put under greater strain.

Finally, there is the option of adjusting the saddle and handlebars horizontally. The most common method is to drop a plumb line from below the rider's front kneecap. If the cranks are horizontal, the saddle is moved horizontally so that the plumb line falls through the axis of the front pedal. This method provides an approximation, but is controversial as it overemphasises the role of gravity (a recumbent cyclist would not make any progress according to this rule). In practice, the plumb line often falls behind the pedal axle and the position is still efficient.

It is better to determine the optimum horizontal position by analysing the rider's centre of gravity on the bike. The optimum position minimises the static holding work by balancing the drive and holding forces. If the position is adjusted so that the centre of gravity is above or just (up to around four centimetres) in front of the bottom bracket, the rider is well balanced. Positioned in this way, the rider's centre of gravity is usually exactly above the pedal axle when pedalling horizontally (maximum lever arm, gravity helps with propulsion). If you adjust the saddle to adjust the centre of gravity on the bike, the handlebars should be moved parallel so that the seat length is maintained.

ADAPT SLOWLY
Once you have found your ideal sitting position mathematically, the real work begins: the practical test. After all, the body has become accustomed to the previous position - which is particularly disastrous if there is a wide gap between the previous and desired posture. This can lead to the movement sequence no longer being smooth: for example, if the calculated seat height turns out to be too high in practice - recognisable by the angular step, where the pelvis tilts back and forth sideways. As you often don't notice such "quirks" yourself, you should ask fellow athletes to take a look at the movement sequence.

In principle, you should only approach a new position in small steps - which is partly due to the material. The design of most modern frames prevents this, as their steererless Ahead stems often force the rider to overreach. The frames are orientated more towards the professional than the amateur rider.

EXPERIMENT A LOT
It would therefore be very useful if there were more stems with adjustable height and length. This would make it easy to "experience" the effect of differences in position. At the moment there are only two functioning models on the market: The VRO system from Syntace is light, sophisticated, durable and length-adjustable up to 50 millimetres. The Ergostem from Look can be adjusted in height (up to 120 millimetres) and length (150 millimetres), but is heavier than the VRO.

What remains? Have the courage to try out different things. Test a stretched seating position, experiment with the centre of gravity, check whether an adjustable stem might be the solution to all your problems. And above all: forget the look of professional bikes for a moment. The best way to counter stupid comments from fellow cyclists is to increase your speed. In a good position, this will be easy for you.

(Text: Robert Kühnen)

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