Riding / Manuevering

The concept of riding a bike may seem totally obvious to some but not to others. I put it in the same category as learning to drive. I remember taking Driver's Education in high school. One girl I was paired up with in a car always waited too long to make corrections in her steering, she then made jerk-motion corrections that were always an 'over-correction'. This usually dominoed to a fairly bad situation and the instructor would stop the car. I see this on the trail as well.

Riding is easy, so don't make it seem hard. Be smooth! Don't grip the handlebars so hard it makes your hands hurt. Completely unnecessary. You only need enough grip to keep your hands from moving around on the bars and to be able to navigate. Don't use jerky motions. Jerky motions are generally not good. It's easy to over-react / over-compensate with a jerky motion. Worse, jerky motions increase possibility of bad things happening, such as breaking a chain or bending a deraileur, losing balance or losing traction, or even getting hurt. Jerky motions also cost more energy than smooth motions, they burn you out and wear you down faster.

Compensate as you need to, don't let errors build up. Lean slightly into gentle curves. Learn harder into tigher corners. Pedal with a consistent rhythm, do not pedal and then brake and then pedal and then brake. You can pedal around the curves too! Your bicycle should have enough clearance from the ground that curves are nothing to worry about. Coast or pedal downhill as you like, always pedal uphill.

All I'm trying to get across here is be mellow about the trail. If you approach a lazy s-curve, roll through it in the form of an s! Simple as that! You aren't restricted to straight lines! Just flow with the trail, and enjoy!

Having said that, perhaps you wonder about my statements about jerky motions being a destabilizing factor and using more energy. Read on if you are interested.

Let's take a sideline and talk about physics. In physics everything is viewed as closed systems. The systems have many limitations placed upon them and contain finite resources. A system could be our universe, with limitations like the speed of light, the force of gravity, density of matter etc. In our system, energy is the finite resource. Everything that happens destroys energy, leaving the system resource poorer. Even worse, the common residual of the passing of energy is heat. This heat is trapped in the system and degrades it. It all goes towards a state of very low energy and high heat, a killing situation.

Believe it or not, everything around you is the same way. An example, factories use energy to create gasonline. Engines burn gasoline to do work. Work is done and heat is created. A process has to be added to keep the engine sufficiently cooled so it can continue to work. This removes energy from the engine that it 'could' be using to do work, and thus less work is done. If it is a car, many other processes are included for human comfort such as air cooling, power steering, power brakes etc. Each of these uses up energy that 'could' have been doing more work. Thus the engine has to be more powerful to handle all the comfort processes as well as do the required work. Bigger engines mean more gasoline is needed to be burned. The meaning of all this? We use our raw resource energy to create energy in a liquid form for our engines to convert the energy into mechanical form that can be used to do work. And every step of the way there is more and more heat being trapped in the system, heat that must be dealt with by introducing cooling processes that require more energy to cool the system (all cooling systems merely move heat from one location to another) and therefore creating more heat (just in another location).

This process never stops. There is no way around it. The best we can do is make the system as efficient as possible, and mathematics tells the best possible system (without superconductors and buckyballs) can only be around 70% efficient. Efficiency that we see around us can come in the form of higher gas mileage, better lubricants and bearings, reducing air flow resistance, etc. (what are superconductors or buckyballs? you'll have to e-mail me)

With me so far? All systems have a limited supply of resources. Usage of resources always results in heat. Heat kills the system.

An area that is important is a concept known as 'jerk'. We are all familiar with motion. Start at point A (position), accelerate (acceleration) to a certain speed (velocity) and travel (motion) towards point B (position). Nearing point B, apply a negative acceleration and come to a stop where we want to be at point B. That covers position, velocity, and acceleration, the components of motion. That's where most of us stop, even if we are taking high level math courses in college. But there is a fourth component, jerk.

It takes an acceleration to turn non-motion into motion, obviously, and here is the key. At the instant of the beginning of acceleartion (or negative acceleration, or sudden halt due to an outside force, or drastic change in motion), there is a jerk, there is a moment when the static 'position' is changed to a dynamic 'acceleration' resulting in motion at a certain velocity. That jerk can be easily seen in a train pulling from the station. As the train pulls forward, all the cars do NOT simultaneously move with it. Each car is jerked into motion, one by one. You can count them down the line by the sound alone. If the train engine started off too fast, the jerk component would over-ride the stability of the system and the cars would break loose from each other. That jerk component is HUGE because the cars have a great deal of mass and it takes a lot of force to get them into motion.

Weight-lifters (I am not making any attempt to be politically correct, weight-lifter/body-builder/body-scultper call it what you like it's all the same thing in principle) avoid jerk at all costs. Jerk means the difference between successfully moving a weight or force and ripping tendons or even muscle fiber.

Therefore, in any energy consumption equation, the jerk component has to be taken into consideration if the model is to be accurate. Also, jerk has to be taken into account with material strengths or sheer factor. The greater the mass, the greater impact of jerk. OR, the higher the number of repetitions, the greater the combined impact of jerk. This is where we come in as cyclists or just human beings.

The simple fact is that 'jerk' is a dangerous component and it is part of everything you do. It robs energy and weakens the system, possibly resulting in damage. Always minimize jerk throughout your mountain biking, if not in everything you do in life. You'll reduce all types of injuries, stay fresher, and have greater impact on the world around you.

Be smooth...