In September, company "The Gym Ltd" gained permission to put a gym on the ground floor of Gilbert Square flats (the old Safeway/bowling alley site) at the junction of Pinner Road and Station Road, North Harrow.  According to their website www.thegymgroup.com it will open in March 2013. 
Proposed opening hours are 24 hours a day, 7 days a week. 

Headstone Residents' Association (North Harrow)
www.thra.co.uk