Dozens of BAE Systems staff donned costumes and pounded round Portsmouth Naval Base in warm spring sunshine.
The Royal Navy and Royal Marines Children’s Fund will benefit from Thursday’s action, and from other fundraising done in the next two years.
The 3,000 workers at the base have opted to support the charity, based at Castaway House in Twyford Avenue, Stamshaw.
While most runners left the corner of Daring building in shorts and T-shirt, one man was walking with two stout sticks.
Sean Collins, 39, groaned his way past the start line under 300lbs of lifting weights.
The engineering manager from Cosham, Portsmouth, said: ‘I wanted to make it a challenge to remember, so I decided to run with extra weight.
‘I was looking at the 30lbs the Royal Marines carry on their qualifying runs, and I thought it would be good to take a larger amount.
‘It’s not me saying I can carry more than them, it was just a challenge I wanted to do.’
Running ahead of him were a team clad in heavy clothing and breathing apparatus from BAE’s rescue team.
Chief Petty Officer Mac McColloch, 42, on secondment from the navy, said: ‘It was a bit tough running in the heavy gear but it was for a good cause.
‘I served most recently in HMS Ark Royal, and while I’ve never needed the charity it’s important to have the support there.’
The BAE staff were launching their first Charity Challenge programme since the company was renamed from BVT.
The BAE site at Broad Oak in Anchorage Park supports the Royal British Legion, reflecting the defence giant’s wish to link up with local forces charities.
‘The Royal Navy and Royal Marines Children’s Fund gives invaluable support to local children and we are excited that they are our partner charity for this fundraising campaign.’
Clare Scherer, of the children’s fund, said: ‘We are delighted we have been chosen by BAE Systems.
‘With increasing numbers of Royal Marines and Royal Navy being deployed in Afghanistan, we are seeing a resulting impact on their families and an increased demand for our support.’
The charity provides support including childcare, special needs education, days out and in-home support in times of crisis.
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