If you can't find a wetsuit to borrow, there are some local triathlon shops and online triathlon stores that rent wetsuits. Be sure you rent a wetsuit specifically made for triathlon and not scuba diving. They are not the same.
You might be able to find an inexpensive used wetsuit to purchase in your triathlon club's classified ads.
Of course you can purchase a new wetsuit as well. This is the way to go if you have an inkling that you will fall in love with the sport. Perhaps you've already fallen in love?
In any case you need to do at least one practice swim, and preferably more, in the wetsuit before race day. Wetsuits change your body position in the water and simply feel different. During practice you will find out if there are any hot spots or areas where the wetsuit rubs into your skin. Additionally, practice quickly taking off the wetsuit, like you will on race day. Lubricating your body with a stick-type body lubricant, a vegetable spray or an ointment helps the wetsuit peel off easier.
The common ointments, such as Aquaphor, can be used on the hot spots to prevent rub marks and blistering.
So, the wetsuit is only for the swim while the tri suit is worn under the wetsuit and is your primary garment for the entire race.
Hope this helps. Have a great race and let me know how it goes.
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