Body Positions and Movements.
It’s better to keep your elbows up and out away from your sides because it gives you better leverage factors over the bike. Try this simple test to feel the difference. Sit on your bike and hold the handlebars with a low grip and low elbows. Then move your upper body back and forth as hard as you can, then do the same from side to side. Now grab the handlebars with a high over grip and high elbows. Perform the same two tests. Which way feels like you have more leverage over the bike? And keep in mind that factor multiplies when you stand up.
Another body position technique is sitting forward. The reason you want to sit forward is because you want to sit right over the pivot point of the bike, in the central location. This way if you lean your upper body forward you are putting more weight to the front of the pivot point, if you lean your upper body back you are putting more weight behind the pivot point. When you are sitting back too far (behind the pivot point) your weight will most likely stay behind the pivot point even when you lean forward.
If you haven’t been doing these and other body position techniques correctly they may not feel good to you at first but after you get used to them you’ll develop more control and therefore be able to ride better and faster. The correct Body Positions and Movements are definitely a ground floor foundation that needs to be perfected if you want to advance. It’s so important that I started my new motocross instructional Volume 3 Technique DVD Series with all the techniques relating to Body Positions and Movements.