Exercise is the most effective way to counteract the effects of weightlessness. While microgravity alters the Musculoskeletal, Cardiovascular, and Neurosensory systems. Though space adaptation is different from astronaut to astronaut. These potential changes have a impact on occupational tasks, as well on their health and fitness. However, the detrimental effects were more significantly observed in long space missions.
To minimize deconditioning effects in cosmonauts and astronauts, scientists proposed In-flight exercises coupled with food supplementation, can counter the effects of microgravity. On an average a person in space will lose calcium from bones each month is equal to a menopausal women does in a year. A deconditioned heart and muscle need to work harder or sometimes leads to tear in tissue once astronaut faces gravity on earth. There are other factors like orthostatic intolerance caused due to Hypovolemia and cardiac atrophy .
In an Pre-Flight scenario the crew starts with their training roughly 9 months prior to their flight. The crew exercise capacity was measured on a standard stationary bicycle and the intensity of the exercise is increased for every 3 minutes with increase in workload. Finally the maximal exercise is determined by the maximal uptake of oxygen. It is also found that at 70 percent of the heart rate crew could function normally without any issues.
On the International space station crew spend two hours for exercise and 30 minutes for post personal hygiene. Generally, crew who were on longer space missions return to earth with Muscular Atrophy, Cardiovascular Deconditioning and Bone loss. For instance, after 180 days mission the muscular strength can decrease anywhere between 11-17 percent, muscular endurance by 10 percent and bone mineral density to 2-7 percent.
|Day 1||Day 2||Day 3||Day 4||Day 5||Day 6||Day 7|
|Resistance||35-60min||35-60 min||35-60 min|
|Aerobic interval||32 min||15min||35 min|
|Aerobic continuous||30 min||30 min||30 min|
The exercise equipment developed for the shuttle includes: Treadmill, Bicycle Ergometer and Advanced Resistance Exercise Device (ARED) .
The treadmill is used to mimic walking and running on earth. For ambulation on treadmill the crew is required to wear a especial shoulder bungee harness system that connected to the treadmill and held the runner in place, during use. At the start of a mission, the load is set at 60 percent of the crew body weight. The load is increased throughout the mission until it is at 85 percent to 100 percent of the weight. A portable computer monitors heart rate and other vital signs while the crew is using the equipment.
Cycle ergometer doesn’t have a seat because astronauts can’t sit in zero gravity. Instead, the crew can snap their shoes to the pedals and tether themselves to the bike with a seatbelt in order to cycle upright and obtain the aerobic and cardiovascular benefits. They can adjust the workload and change speeds to hit their target heart rates.
advanced resistive exercise device
It is a roof of Unity. Designed for weightlifting in a weightless environment, it consists of two evacuated, pistol-driven canisters with a flywheel mechanism. Crew can configure the equipment to perform exercises like dead lifts, squats, biceps curls, and calf raises.
The medical team on the ground monitor the fitness of the crew and work out how much their condition has changed. They can instruct the crew to alter their exercise programs, if required.