When we exercise on an aerobic machine (elliptical, treadmill, bike, stair stepper, etc.), our intent is to condition our cardiovascular system. In essence, we are concerned with our heart rate, breathing and fatigue. It is all about our heart and lungs. However, seldom do we consider the biomechanics needed to reach our workout intensity. Consequently, people are hunching over the machines, leaning forward and getting hurt. Not good!
Six Posture Related Injuries from Aerobic Machines
One issue: Ligaments are permanently stretched This issue is common in the pelvic area when vertical alignment from the ear to the ankle is not maintained. Also, this happens when we use the elliptical or stair stepper when our feet are too far back and our pelvis is tucked under.
Another issue: Cartilage damage due to abnormal friction Knees are a prime target for this type of damage. When the hip and ankle are misaligned, the soft tissues within the knee joint wear down with every repeated movement.
A third problem: Disc injuries from vertebrae misalignment If we round our shoulders and upper back, this puts additional stress on our spine. As a result, this can cause our discs in our neck and lower back to bulge or herniate.
Fourth: Nerve damage, including worsening impingement and imbalances, causing headaches, numbness and tingling
We often experience this in the neck when we have overstretched our muscles because of a head-forward position.
A fifth issue: Arthritis development or progression in weight bearing joint There is a kinetic chain of movement from the vertebrae of the spine to the shoulder, hip, knee and ankle. Each affects the other. If we have imbalances in our joint position, this will create wear and stress in the body. Eventually, this leads to cumulative trauma and pain.
Finally: Imbalanced muscles Opposing muscle structures develop unevenly. In other words, some become short and weak, while others become elongated and weak. When we lean forward while walking, this will impair gluteal muscle function and will create uneven development in the lower body. Instead, having an aligned posture would increase muscle activation and establish balance between the upper and lower body.
Head/Neck Position First, note that your head should be centered between your shoulders, resting on the top of the spine without going forward. Now, check to make sure your ears are level from left to right. In essence, they shouldn’t tilt to one side. Next, look out on the horizon, not down at the screen in front of you. When you do this, it will help to maintain the cervical curve in your neck and reduce strain on these vertebrae.
Shoulder Position First, check to see that your shoulder blades are drawn down and together towards the spine. This will open the chest, allowing for better oxygen exchange and increased lung capacity. Also, your shoulders should form a 90 degree angle with both shoulders level. If your shoulders are instead rounded, this will increase the stress on your upper neck muscles on the back and front of your body. Additionally, this creates muscle disparities. In other words, your the neck muscles in the back will lengthen, and the muscles in the front will shorten. Finally, shoulder rounding also internally rotates the humerus (top of the arm bone), which causes the anterior, medial and posterior deltoid muscles of the shoulder to develop unevenly.
Foot Placement When you use the elliptical trainer or stair stepper, your foot should be placed directly under your hip. This will create vertical alignment from the hip to the ankle. For most people, this will mean moving the foot to the front of the platform. If your knee angle is too small, you will feel pain. In order to combat this, move your foot forward until you’ve hit the right angle. Then you should be in the correct position.
Hand Placement Your arms should hang naturally down along side your body with the shoulder, elbow and wrist in alignment. When you use handles for the treadmill, stair stepper or recumbent bike, grab the handle so that your arm is in this alignment. Also, on the stair stepper, do not press into the hand rails for additional support to aid the lower body. Instead, reduce the intensity of the exercise.
