Treadmill vs. Outdoor Land Walking or Running February 3, 2007Posted by Lisa Sabin in boston marathon, fitness, Injury Prevention, marathon, running, Treadmill Running.
1. How is treadmill walking/running different from land walking or running?When walking/running on land, you have to contend with specific environmental conditions; for example, weather conditions such as wind and rain, the changing cant of roads, other traffic, hard sufaces and wet slippery terrain.Treadmills cannot prepare you completely for running outside. The variation of running outside on different surfaces is actually healthier for your body. Changing the surfaces, speed and incline or decline keep the body from suffering from overuse.When on a treadmill, your mind and body must contend with a running in a confined space, belt lag, vibration and possible boredom.Mechanically, your body must contend with landing on a surface that is moving in the opposite direction. The rearward rolling treadmill decreases the need for your hamstrings to pull your upper body forward; however, your hip flexors have to work harder to control your foot being dragged backwards and in pulling your lower leg forward. A decrease in push off ability (caused by the moving belt) further increases the load on your hip flexors.The treadmill sets an artificial pace that is unchanging in light of indirect factors (e.g., headwind, terrain changes etc). It’s easier to maintain a running pace that would be more difficult outside. For this reason, many who do a lot of training on a treadmill have difficulties in applying the same speed to the hard surface. They may find that they aren’t able to maintain the same pace, and as their mind wonders, their pace decreases.The impact on skeletal bones may be less on a treadmill because the surface is more flexible and the stride belts cushion the impact.In terms of energy usage, most research suggests that there is no significant difference between treadmill and land surface running.2. Is running/walking on a treadmill dangerous?As with any form of training, overuse injuries are a concern. Mixing up running and walking surfaces help prevent repetitve overload injuries. If possible, alternate between walking/running on the treadmill and walking/running on land. Try utilizing different cardio machines to add variety.Natural gait and proper body alignment can also be adversely affected. These alterations in gait techniques can be caused by an incline which is too steep or a pace which is too fast or too slow. Body alignment and posture can be compromised. Incorrect alignment can alter the correct force transfer along the body and increase the stress on joints and muscles.When your foot strikes the treadmill belt, the force through the limb is transferred to the belt, which is travelling in the opposite direction. This impact force causes the belt to stop momentarily (even reverse direction slightly) before belt speed is reinforced by the motor. The amount of belt lag varies with the power of the motor, looseness of the belt, belt speed and weight of the individual. The sharp, reverse-direction acceleration, for a high repetitive duration, may not be complimentary to your body.The smaller and lighter the treadmill, the more the vibration (especially at the higher speeds). This can be clearly felt when running on a cheaper domestic treadmill compared to the more expensive treadmills found in health clubs. Whole body vibration (over a long period, like truck driving) has been linked to lower back problems.3. Can muscle imbalances result from continued use of treadmills in training?This depends of the individual’s technique, previous injuries, speed of training, and type of treadmill. If you have an existing muscle imbalance or injury, the treadmill may not help. The lack of variation may will only prolong recovery.Thus, in order to prevent muscle imbalance, variety is the key. Either alternate training surfaces or cardio machines. If the treadmill is your only option, alter your training methodology (Inclines, Speed, Interval, and Long Slow Distance, etc).Sources:Dave Schmitz PT, LAT, CSCS, PESHealth Services at Columbia