Muscular strength is the ability to exert force. The benefits of having good muscular strength would be you have the ability to perform everyday tasks such as lifting heavy things. Having good muscular strength means that you are strong and self-sufficient. Having good muscular strength throughout your life will also be good when you are older because your physical state will deteriorate more slowly.
The Cardio respiratory fitness is basically how well your body can transport oxygen around itself and how well your body can take in the oxygen. Swimming back stroke or any stroke at all is an example of cardio respiratory fitness because after swimming for a short period of time you may start breathing more rapidly which means inhaling more oxygen.
In some sports there are times when you are not moving your arms or not moving your legs. In swimming you are always kicking and always doing a stroke with your arms. Muscular endurance means that you are performing a task repeatedly, which you are with swimming because you have to do the stroke again and again until you are finished the race. The benefits of being a person with good muscular endurance are you will be able to do things for a long time.
To swim any stroke you must have flexible shoulders, especially in butterfly because your arms must go in full circles. Flexibility in the wrists is necessary because you need to be able to push the water back and propel yourself forward. Flexibility in the ankles is important because to get the best stroke possible you need to keep your stroke in a stream line position which means all straight and all together to glide through the water the most efficiently. This includes having your feet pointed when you are kicking. The benefits of being flexible are having the ability to perform everyday tasks without being in pain, even things such as bending down. Being flexible also reduces your risk of injury because if you are flexible and you need to do the splits you might be able to do them instead of pulling a muscle in your leg.