"impact tool" joint pain

i know this is not steroid related but was unsure where to put it.

i posted this on the motocross/arm pump thread but have also started a thread of its own for an answer.i apologise for double posting:-
(i said i apologise for double posting)

my mate works for a railroad company and suffers from severe arm pumps from high impact drills/tools which resulted in him having to take time off work.his doctor diagnosed "arm pump similar to that experienced by motocross riders.

is there anything that will help relieve the sore joints he gets from vibration?

i thought of glucosamine and chrondroitin but did not know if this would help or if there is something else that would help.

any advice would be appreciated as it is his job and he has no way of avoiding using high impact tools.

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