I've been swimming for almost a year. My free style stroke is decent, but my resistence is terrible. I need to rest after completing every lap. I am wondering if the using of a mask and a snorkel will help me to improve my speed and my technique.
absolutely not!
Breathing is an essential technique that you need to practice as much as possible. The reason you need to rest lies on two things: you have poor stamina at the moment and bad breath control. Swimming with a snorkel will only prolong your problem.
If you've only been swimming a year, you probably need to work on your technique frequently. I'd recommend drills over going out an purchasing swim gear. I want you to try the shark fin drill, and practice kicking on your side.
Shark fin drill:
A freestyle based drill
Regular kicks
When you use your arms, you go in a regular pattern, except when your arm comes out of the water, bend your elbow sharply up in the air like a shark fin and bring your finger tips to your brow, in a salute like manner. Hold for 3 seconds, then move on to the next stroke and repeat
Side Kick:
Have one hand outstretched in front of you and roll onto your side. Tuck your chin to your chest (proper swim position) with the back of your side of your head resting on your bicep. Other arm should be resting on your side by your thigh. When you need to breathe, turn your head (without lifting it from your arm) and breath. This will be a difficult drill to encourage proper strong kick motions when you turn to breath, and will reinforce good breathing techniques.
Don't listen to the person who recommends using the snorkel because their sprinters use it. When you become more advanced, exercise gear will start to supplement your work out. Snorkels have no place for a beginner to the sport. I personally wear 5 pound weights on my wrists and ankles when I swim, but I would never recommend that to anyone but the most advanced of swimmers