Unison members at both centres voted by 85 per cent on an 83 per cent turnout to continue their fight against being fired and rehired by Sandwell Leisure Trust to remove them from national pay, terms and conditions.
Unison members have already undertaken three one-day strikes in a dispute that has been ongoing for more than 12 months and is officially the longest in Sandwell history.
Sandwell Unison branch secretary Tony Barnsley said: "Our members are determined to continue their fight against being unnecessarily ‘fired and rehired’ against their will whilst the Trust still has £3.5 million in the bank.
"Despite promising not to make any further changes to terms other than pay until March 2022, management have now sent the trade unions proposals to make any Covid-related absence count towards targets, and triggers. This proposal effectively breaks their own promise."
A spokesman for the trust said: "Sandwell Leisure Trust is committed to safeguarding the future employment of our staff and ensuring the long-term sustainability of the services it manages in Sandwell.
"Around 58 per cent of our workforce live in Sandwell and we are committed to remaining a good sustainable local employer for local people delivering local services."