My friend is a sailor and has a bit of a problem with designing a training plan for himself.
While at home, he does various activities, he likes swimming and rock climbing, sometimes he plays squash. He wants a trainign plan to keep him fit when he's at sea for 3-6 months.
There are problems with that. He has to travel light, so he cant take much equipment with him. Think something that would fit in a handbag or a small rucksack. He cant be running around the deck to make any reasonable running sessions, and he cant really do the usual bodyweight exercises. At the ocean the waves are so strong most of the time, that its either very hard or very easy to do a pullup for example, as the ship is going down or up and aiding/hindering the efforts.
What would be a good general-fitness training plan for such an environment? Maybe some resistance bands or springs...? Would that provide enough resistance?