In some ways this is really self-care. It is also part of protecting everyone involved in the craft group from harm.
Questions you need to answer
Can whatever is being moved be split into smaller and more manageable sections. For example is a single alrge box necessary to could the same items be carried in a number of smaller boxes.
Where will heavy items be put so that they are more moved or lifted anymore than necessary?
What aids are available. For example do you have a trolley or a box with wheels.
Is it too heavy for one person to move on their own or is it a two person job?
Do the things around you make the task harder? For example do you need to go through doors or up steps or over thresholds or deal with any other obstacles?
Would a manual handling course make sense?