Two people had to be rescued after they defied the lockdown and got into difficulty on a boat while under the influence of alcohol.
HM Coastguard said the incident happened on a day when the number of UK call outs soared by 54%.
A total of 97 incidents were recorded on Friday, which was a public holiday for VE Day, including 16 in Scotland.
Coastal operations area commander Ross Greenhill said reckless behaviour by a minority is putting lives at risk.
The figure was the highest recorded since the lockdown started on 23 March and compares to a daily average of 63 for the previous month.
As well as the boat incident, Mr Greenhill said crews have helped people who have been caught out by incoming tides.
Some rescues have also involved a helicopter.
He said: “This puts quite a large number of officers at risk. We want people to stay at home and save lives.”
Mr Greenhill urged people not to exercise in unfamiliar places.
He added: “Don’t go somewhere where you have never been before and you don’t understand the risks. Keep it simple and stay close to home.”
The senior officer said rescues in the current climate not only endanger the health of his officers, many of whom are volunteers, but also their families.
And he stressed irresponsible actions put the NHS under strain when all resources should be focused on combating the pandemic.