Long Term Sitting When you sit, your pelvis rolls backward and the small of your back flattens out. This increases the pressure in the discs of the spine. (In this position, the discs are less prepared to handle the vibrations from the vehicle/machine you are sitting in. Ligaments in your back help to hold the spine together as you move. These ligaments will stretch and slacken if you sit down for a long time. After standing up, they remain slack for a while and cannot support the spine as they normally do. If your seat is not correctly adjusted, you could develop pressure points (area on the skin that is highly sensitive to the application of pressure). in the buttocks and back of the legs, as well as muscle strain in the low back. Continuous upper back and neck muscle work is often required to hold the head in position, especially if vibration is present. Continuous muscle activity can lead to muscle strain. Holding a foot pedal down over a long period of time may cause stiffness and spasm in the legs and low back. WHOLE-BODY VIBRATION Bumps in the road cause up-and-down vibration of your automobile or truck frame along the length of your spine. Every object has a “resonant frequency” (the body’s is 3-5 Hz). Vibration from the road is often in the body’s resonant frequency range. Exposure to vibration at the resonant frequency increases the risk of injury. Whole-body vibration stimulates bursts of back muscle activity. This causes neck and back muscles to tire more quickly, and decreases the support these muscles provide to the spine. Even if the muscles are working very lightly, activity for an extended time without rest will lead to fatigue and increase the risk of back injury. Long term exposure to whole body vibration is a common way to herniate a disc in your back. The increased disc pressure from sitting speeds up this process. The International Organization of Standardization (ISO) has produced recommended limits for human exposure to whole-body vibration. Assessments can be performed to determine if your vehicle is within these safe standards. CUBITAL TUNNEL SYNDROME Workers whose occupations require them to drive for extended periods of time may also be at risk of developing a disorder called Cubital Tunnel Syndrome or Ulnar Neuropathy. This disorder is characterized by numbness and tingling in the outside half of the ring finger and the pinky. The ulnar nerve is located closer to the skin’s surface and is less deep than other nerves and is unprotected as it passes along the underside of the elbow making it more susceptible to external pressure. Leaning on the elbow, or constant direct pressure on the elbow may eventually cause cubital tunnel syndrome through repetitive pressure and irritation of the nerve. For instance, resting on the elbow while driving long distances with an elbow rest or on the window can cause prolonged pressure and irritation on the ulnar nerve. HOW CAN YOU AVOID THE HEALTH HAZARDS OF DRIVING? • Literature suggests that if possible, the back of your seat should be tilted at 110 degrees from your legs (i.e. the seat pan) to reduce disc pressure and relax the back muscles. • Keep your suspension system in good working order! You my also want to add extra padding over your seat to absorb vibration. • Adjust your seat and steering to ensure you can press the pedals without moving your low back forward off the back of the seat. • Use a lumbar support. Even a properly-placed rolled-up towel will suffice. • If possible, tilt your seat a notch or two back and forth every 20-30 minutes. This alters the direction and the effects of vibration. But stay high enough to see the road. • Avoid slouching. Here’s a tip: don’t adjust your rear or side view mirrors unless you have changed the tilt in your seat. • If you can, take regular rest/stretch breaks. Only 5 minutes per hour will suffice. • Shift positions regularly while driving. • People who work in driving occupations are often inactive and could gain weight. Being overweight increases the chance of injuring your low back. Find active forms of recreation to keep fit in your personal time. • Avoid driving with your arms resting on the window and arm rests for extended periods of time, switch it up.