If you are not doing beep tests as part of your training you, need to add it. Do it at least once a week. Start to incorporate interval and fartlek training. These methods of training will help you increase your aerobic and anaerobic capacities. Try an interval training method called Tabata, 20 seconds work followed by 10 seconds rest. Repeat 8 times or 4 minutes worth. Rest 1 minute complete 4 rounds.

The Commando