Wetsuits & Fitting
Firstly we should look at how a wetsuit works before deciding on which wetsuit you need for your sport. A wetsuit is constructed using neoprene that is heated up until it expands then cooled and cut. So the material is then cut into lengths needed to put the wetsuit together.
Once you put on the wetsuit and enter the water the neoprene forms a thin layer between you and the water. A wetsuit is designed to let in a little water so forming a barrier between the wetsuit and your skin, this water then heats up to your body temperature and is maintained at this warmth by the wetsuit. The amount of time you can use it for without getting cold is determined by a few key factors such as thickness of the wetsuit, water temperature and quality of the wetsuit you have.
Thickness
This is one of the most important factors to decide upon as it will be the difference between you being warm or cold.
Winter 5/3 wetsuit
In the winter months (December to April) in the UK we wear 5mm / 3mm full wetsuits. This means 5mm of neoprene on the body a 3mm on the arms for flexibility. A winter wetsuit can be used in water as low as 5c and as high as say 18c. Generally in a winter you can last up to 3 hours before getting cold, again this is also dependant on the quality and it is pretty much the more you spend the warmer and more flexible they become. You will also need to buy gloves, boots & hoods.
Summer 3/2 wetsuit
In the UK a 3/2 full wetsuit is deemed as a summer wetsuit however in say Australia this would be a winter wetsuit as the water temperature does not fall to low. So in the UK we tend to use these from April till November when the water is 17c up to 20c. Summer wetsuits are much more fun to wear as they are far more flexible due to the thinner material and you can generally last for about 4 hours. They are good pretty much any type of water sport excluding diving if you are going deeper than 30 metres as the neoprene will compress any deeper making it thinner and less warm. You can purchase pre-compressed neoprene, which will not get any thinner
Shorty Wetsuits
Generally a shorty wetsuit is limited in the UK to the months of July to September and temperatures of 20c plus. These wetsuits have no arms or legs as they are designed to keep the core of the body warm without any restrictions. They are usually 2mm of thickness on the body and 1mm on the arms. Good again for pretty much all water sports.
Fitting
This is a crucial element to any wetsuits working, the fit must be good as if it is to tight it will restrict movement make the material thinner which will cause it to be cold. To big and it will let to much water in and your bodies core temperature will cool to quickly making you cold. Please refer to the below video for a detailed look at how a wetsuit should fit.