1. The space walker (MMU) can make astronauts become independent spacecraft. The original spacewalker was designed for the American space shuttle, but astronauts in the former Soviet Union later used similar equipment. The spacewalker looks like an armchair, with a height of 125 cm and a weight of 100 kg. The spacewalker is connected to the back of the spacesuit. There are two iron arms on the chair, and all the control buttons are on it. By manipulating these buttons, astronauts can move in any direction at a speed of 20 meters per second. The motion thrust of the spacewalker comes from some small nozzles, which can make the nitrogen in two high-pressure tanks spray out. The spacewalker enables astronauts to move freely in space. 2. A kind of sports equipment. Exercise method: Hold with both hands, separate the left and right pedals, and swing back and forth naturally to walk. Main functions: exercise the flexibility of lower limb muscle strength: promote the health of cardiovascular and cerebrovascular systems and cardiopulmonary respiratory systems. A survey conducted by the International Association of Health, Tennis and Sports Clubs (1HRSA}) found that since 1997, the usage rate of the spacewalker in the United States has increased by nearly 200%, and currently 7 million people are using it for exercise. Among them, the ratio of male to female is 60%; 40%。 Adults and the elderly especially like spacewalkers. More than 50% of users are over 35 years old, while the growth rate of users over 55 years old is 300%. The spacewalker is popular because it has the feeling of running but avoids the damage to the lower limbs; Moderate impact, you can exercise your upper limbs as hard as skiing, and the elliptical trajectory is similar to riding a bicycle, but it is not uncomfortable without a seat, and it also increases heat consumption. People can also choose different exercise intensity by adjusting the slope, from walking in the park to climbing up the steps quickly. Vibration training can improve strength and explosive power. In the exhibition of fitness and rehabilitation equipment, the vibration platform is always particularly eye-catching. It can produce high-frequency vibration, and the exerciser has to do squats or push-ups in the vibration. Designers believe that the vibration generated by machines can stimulate the stretching nerves in muscles, thus causing the contraction of hundreds of tiny muscle fibers. Some fitness equipment manufacturers also design vibration into their products. Although the theory that vibration stimulates muscle growth sounds attractive, in the 10 years since the advent of this equipment, no professional athletes or bodybuilders have seriously used it for training, and there is no evidence that the performance of this equipment worries similar products that do not vibrate. Vibration training seems to have obvious warming-up effect on muscles, which can temporarily improve the explosive power of muscles. Practicing movements, instead of many simple movements in muscle life, such as getting up from a seat, requires very complicated whole body coordination to make muscles produce just the right strength and correct movement sequence. This is especially true for complex movements, such as swinging a galvin ball, throwing a softball and running. But people usually don't practice these movements in the gym, but practice muscles in isolation, such as biceps brachii bending and quadriceps femoris flexion and extension. Isolated exercise can improve the appearance of muscles, but it does little to improve their ability to work together. At present, international popular functional training programs, such as "Crossfit", combine track and field, gymnastics, weightlifting and other movements for non-intermittent exercise. Sports physiologists believe that intensive whole-body exercise is stronger than isolated muscle exercise, and isolated muscle exercise can only improve the appearance of muscles. Two effective exercises of waist-abdomen machine experts say that the muscles of abdomen, back waist and waist side are the core parts of human body. These muscles are very important for maintaining functional health and good physical loyalty and reducing the occurrence of low back pain. Fitness experts recommend two excellent exercises to strengthen the strength of the core parts. The first is the side support bridge. The specific way is to lie on the ground. Support the body with the left forearm and left foot as fulcrums, and put the right foot on the ground in front of the left foot to keep the spine in a straight line. Can't sink 1 group hold for 30-60 seconds, then relax and switch to the other side. This action is mainly to strengthen the muscles responsible for stabilizing the spine, such as the lumbar muscles. Electrogram shows that this is the most effective action to exercise lumbar muscles. The twentieth exercise is to push down and lift your arms down. Kneel on the ground. Support your body with your forearms and feet. Keep your back straight. Then stretch your left arm forward until it is parallel to your body, and keep it for 30 ~ 60 seconds, then put it down and replace it with your right arm. This exercise can strengthen shoulder muscles, chest muscles, abdominal muscles and erector spinae. These two exercises are good for strengthening the strength of the core parts of the body, improving the body shape and preventing lumbar spondylosis.