Why wearing a trisuit?
For swimming, cycling and running in the same suit, the trisuit is a staple. Its benefits: dries quickly after swimming and is comfortable for cycling thanks to a pad that does not hamper your run.
Triathlon suits are worn like cycling shorts: with no underwear.
Trisuit, triathlon suit, triathlon trisuit... are there differences?
None! It's the same type of triathlon outfit, a 3 in 1 suit: you pick you preferred term.Just make sure you don't confuse it with the neoprene suit that provides buoyancy and warmth for the swimming portion
Should I put an additional suit to swim?
Yes… and no.
The trifunction suit doesn't provide thermal protection, but the neoprene suit provides buoyancy, an asset for the swimming portion. Good to know: The French Triathlon Federation forbids isothermal swimsuits when the water temperature is above 24°C and makes it compulsory when the temperature goes under 16°C. Between 16 and 24°C, it's up to you.