There are a number of saints named Maximus so you need to be more specific.
According to the Patron Saint Index, the patron saints of babies are:Brigid of IrelandHoly InnocentsNicholas of TolentinoPhilip of ZellPhilomenaRaymond NonnatusZeno of Verona
Maximus of Rome, who died about the year 250 as a martyr, is not a patron saint as per the Patron Saint Index.
There is no patron saint of golf. St. Sebastian is the patron saint of athletics. Another opinion: The patron saint of golfers is St. Andrew.
Saint Kiara is a saint but she is not the patron of anything at this time sorry
The closest I can find is St Bernard of Menthon who is the patron saint of mountaineers.
St. Lucia Filippini is a saint but not a patron saint at this time.
David of Wales is the patron saint of doves.
The patron saint of all sports is St. Sebastian.
I don't know if runners have their own saint, but St. Sebastian is the Patron Saint of Athletes.
There is no patron saint of tennis or tennis balls. All we have is St. Sebastian who is the patron saint of athletics and athletes.
St. Isidore of Seville is the patron saint of the Internet.
Saint Zama is not a patron saint.