If you want to improve your cardiovascular conditioning and endurance as fast as possible then I have two words that will work wonders for your conditioning in this area, hill sprints. Keep in mind this is anaerobic training which most closely resembles martial arts competition which is shorter in duration and involves intervals of explosive movement mixed with lighter movement.
What I love most about this form of training is that it doesn't take long to perform a workout or start seeing real results. But be warned that this is an advanced form of training and you should consult a physician before performing this or any other form of exercise.
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With that out of the way let's take a deeper look at hill sprints.
The only prerequisite for performing hill sprints is that you'll need to have access to a hill where you can perform them. A 45 degree angle or greater hill is ideal and you'll need a distance where you can sprint for at least 10 seconds or up to 20 seconds. You begin by properly warming up and stretching for 10-15 minutes, you can warm up by lightly jogging and stretching out your legs before undertaking the the much harder portion of the workout that will be the sprints.
Once the warm up is out of the way you'll want to do one light trial run up the hill to get a perspective of what your dealing with as well as prepare yourself mentally and physically. Then you'll be ready for the real thing.
Then from the bottOm of the hill, sprint up as fast as you can. This type of training works best using intervals so after your first sprint up hill, preferably for 10 seconds if you're starting out. Then you'll jog down the hill and jog for another minute on flat land before performing another hill sprint and again follow with 1 minute of jogging. You might want to break up your intervals with one minute rest periods if you need to then repeat the hill sprints for five to ten times.
Once you're done you'll want to finish up with a cool down period consisting of some light stretching and walking, (while you're cursing me for convincing you to try this).
You'll obviously want to increase the duration of the sprints every time you train, you can also get really crazy and buy a weight vest. This will enable you to add 20-40lbs of weight to your frame for some hardcore training. But don't say I didn't warn you, this training is extreme and you'll have to be well conditioned and prepared to attempt hill sprints with an additional load.
After 2 months of this type of training you'll want to take a couple of weeks off to prevent over-training.
Hill Sprints For Martial Artists HILL