Which is the act of refraining from having sex?

Abstinence is your answer Gradpoint

the suction machine and tubing is the equipment that should be left behind and should be most easily accessible.

during longer space exploration trips, crewmembers may develop vision impairment risks and short-term cardiac atrophy or a decrease in the size, strength, weight, and activity of the heart during space flight because they can experience microgravity. in addition, the long-term medical condition is loss of bone mineral density and radiation exposure.