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5. Condyloid joints. These are similar to saddle joints in the movements they allow. The wrist is an example. 6. Gliding joints. These allowmovements such as the ones made by the joints found in your hand. Your muscles connect your bones and joints and enable you tomove. There are two types of muscles: 1. Flexor 2. Extensor Let’s say youwant to pick up a glass that’s on a table. Your triceps (an extensor muscle) contracts so your armbends at the elbow (your arm straightens) to reach the glass. To raise it to take a drink, your bicep muscle (which is a flexor) retracts your armback toward your body. HOWIMPACT TRAINING AFFECTS JOINTS Studies done in 2014 and 2016 by researchers at the US National Library of Medicine and National Institute of Health found that walking on a level surface produced about .5 times body weight of joint force on the patellofemoral joint (located between your kneecap and your femur bone). Jumping, however, produced 20 times body weight on the same joint. In this example, walking, which is low impact, puts less strain on the joint than jumping, which is high impact. This is why high-impact training is associated with sports injuries like a torn anterior cruciate ligament or a sprained ankle. This isn’t to say that high-impact training should be avoided. In fact, when used in conjunction with low-impact training, it can be beneficial. At the same time, when overused or done with improper technique, high-impact training can lead to injuries or long-term conditions like arthritis. If you’re new to high-impact training, seek guidance from a coach or trainer before you start.

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What is Low-Impact Training?