It could cause problems on knees and feet if the weight and force are not used properly. Exercise stationary bikes These are mounted bikes which are steadily attached on the ground. A great way to get a cardio workout at home, especially for beginners since it does need special skill to operate or use. According to the book "Make Over Your Metabolism" by Robert Reames, you can "manage your weight, shape, and appetite by providing a time-efficient, fat-burning exercise plan, a super simple nutrition plan that will optimize your metabolism, and lifestyle strategies that will help correct red flags that interfere with a healthy metabolism. You do not need equipment that will only be left non-useful in the garage or elsewhere because the allotted space inside the house will not be able to accommodate all the equipment. Tread mills for example take a lot of space. Know what cardio exercise equipment you need and which ones you can easily install and use at home. Elliptical trainer machines offer other features that may not be present in common treadmills. It allows you to exercise in the normal forward motion but can also present routines in a reverse direction. The change of direction will give you the chance to target various sets of muscles thus your workout is revved up to higher levels. These settings are similar with the gears found in regular bikes and can be used to increase the level of your workout. There are two types from which you can choose namely upright and recumbent. For an upright model, you are seated just as you would on a standard bike. While some prefer this, there are others who complain of too much pressure on the groin and lower back even if these individuals have only spent a short time on the bike. On the outside it may look fine, but the interior of the machine may be starting to have small problems. For example, if equipments with springs are exposed to dampness, the springs may get rusty and may lose its ability to compress and bounce back. In worst cases, equipment problems or failure could happen in the middle of the workout, causing accidents.