The answer is that it takes most people about eight weeks to train for a 10k race, but it is certainly possible to do one with less time to train. If you want to train for a 10k in 4 weeks, you will need to step up the intensity of your training regimen significantly. Eight weeks is the minimum recommended training period for this type of event because it allows for enough time to train intensely without having to worry about injuring themselves in the process.