Published: 00:01, 01 September 2014 |
Updated: 10:19, 01 September 2014
Donna Govan and her partner became members of Medway Park, in Gillingham, to take advantage of the slot exclusively for adults between 7pm and 9pm.
But they arrived just after 7pm to find youngsters "jumping in and splashing around".
The only child-free session is now in the middle of the day.
Ms Govan, of Marlborough Road, Gillingham, said: "I saw the adult run as a wind-down after work, but now the timetable has been changed it's at a time when most adults are at work.
"Also, as I am not a strong swimmer, I could swim without the worry of children jumping about. We have nothing against children, but I am sure Medway Park will have a number of members, both strong and weak swimmers, who enjoy a swimming session without children in the pool."
Ms Govan is also angry the times were changed without any notice. She feels the amendment broke the terms of her membership contract as it was a "major factor" in joining the Mill Road sports club.
She said: "We enjoy our visits to the centre, but feel we may have to find another centre as Medway Park is no longer meeting our requirements."
A Medway Council spokesman said: "These sessions have been changed to lane swim sessions and are now open to anyone wishing to swim lengths without disruption.
"The lane swim session is not a general swimming session and anyone causing disruption and not intending to take part in lane swimming is asked to leave.
"The centre's timetable is often revised and is subject to change."
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