A 3k run is 3 kilometers in length. This is equal to approximately 1.86 miles. The amount of time it takes to complete a 3k run depends on how fast a person runs.
If a 150-pound person completed a 3k run, that person would burn 211 calories. The number of calories burned varies slightly depending on the weight of the runner. Runner's World recommends focusing on the length of time a person runs rather than the distance. This is because the health benefits of running come from keeping the heart rate elevated for a certain period of time rather than covering a certain distance.