Stacking is indisputably the hardest part of mountain biking and riding a bike in general. Having the ability to prevent falling off makes you a faster, safer and healthier rider. When we ride a bike, we slow down because we think we are at risk of having a fall, so being able to prevent this is going to allow you to hit the trail that much faster.
Before I get into any anti-stack remedies I thought I'd run you through my latest accident. I was riding on some local fire trails, yes fire trails, when a 90 degree off camber corner got the best of me. Mid way through the corner my tyres slid out from underneath me, so I rotated my torso so that I was landing on my front, with the intent to brace myself with my arms on impact. Here, my first point of contact was my left knee, followed by my arms, chest and chin. My chin hit the ground with only low to medium impact but was enough to split the skin. In my landing plan, I took into account my direction, the ground surface and most importantly my speed. I was fortunately not going very fast so I had plenty of time to pick my landing technique. Please keep in mind that aiming to land on my front was appropriate for this crash and in most cases I would not recommend this form of landing.
How To Eat Dirt
A lot of the time you fall with very little time to think, but in order to land safely, you need to put some strategy into this. If you have enough time, run out of it before you hit the ground. If not, try to relax your body and roll when you land because if you are stiff, you are more likely to break something or get bad abrasions. Before you fall over, try to find a soft patch of pine needles, grass, leaves or at least somewhere without any rocks or sticks to land on. If you find yourself going over the handlebars in a superman position, instead of landing on your hands, risking injuring your arms and shoulders, try and perform a commando roll to minimise impact.
Improve your reaction time. There are plenty of exercises out there to help in improving your reaction time so run an internet search to give you some ideas. Having a quicker reaction time will give you more time to plan your landing, reducing risk of injury.
Strengthen your shoulders. Cyclists are prone to shoulder injuries due to shoulders often being the first contact point in a fall. Be sure to include upper body and shoulder strengthening exercises in your training regimen to reduce potential injury and to give yourself a bit of extra body armour.
Practice your commando rolls. Get on some soft grass or foam mats and practice rolling. Start with your hands and knees on the ground and push yourself to give you a smooth, controlled roll. Progress to rolling at speed or from a leap and even from different angles so you are rolling sideways or pulling out of obscure positions. This will improve your ability to cancel impact shock in the event of a crash
Practise the track stand. Having good balance from practising the track stand will make you more stable when riding at speed and through tight technical sections, greatly reducing the risk of having a fall. I have done an article on the track stand here.
Wear appropriate armour. If you have a pretty hardcore riding style or find yourself crashing a lot, look at investing in some knee/shin and arm/elbow protection. You can get neoprene styles which may be more comfortable when peddling, or you can opt for big hitting free ride protection.
If you get on a bike, you are going to fall of at some stage. By following the precautionary steps listed, you can minimise the impact of hitting the dirt and maximise your on the bike time.