How can I improve my cardiovascular fitness in 2 weeks?

Hi Daniel,

To improve fitness, assuming you were in good shape before the injury and have some past training under your belt, you need to just do a progressive exercise routine.

Whatever activity you choose, start off quite moderately and add a bit of extra time and a bit of extra intensity to each workout. Gradual progression allows your body to keep up to speed with recovery and repair whilst it re-adjusts to the stress of training. For an excellent review of this subject by one of the most famous early adopters of periodization (progressive exercise designed to peak athletic performance for a certain date), check out Tudor Bompa's writings.

You don't want to jump right back into the training volume and intensity that you were doing previous to your injury or you're likely to just get injured again.