Body Mass Index (BMI) is used by the World Health Organization (WHO) to assess overweight and obesity. This indicator is considered valid for men and women aged 18 to 65.
Below you will find a one-click BMI calculator, then simple benchmarks to see which category you fall into, plus a few practical tips for running training.
In general, an “ideal” weight is often linked to a BMI between 18.5 and 25 kg/m². Still, BMI alone is not enough. For a clearer picture, it should be paired with a body fat measurement (which requires a specific device). A very muscular person can land in the “overweight” category even with low body fat.
Contents
BMI Calculator
Below 16.5 kg/m²: severe underweight
Between 16.5 and 18.5 kg/m²: underweight
Between 18.5 and 25 kg/m²: normal weight
Between 25 and 30 kg/m²: overweight
Above 30 kg/m²: obesity
How to Interpret BMI for Runners
Among consistent runners, it is not unusual to see BMIs around 18.5 kg/m². Just be careful not to go too low, otherwise your body can become under-fueled and weaker. To recover well from training, you need enough hydration and enough calories from quality nutrition.
As a reminder, BMI is your weight in kilograms divided by your height squared in meters. In other words, you divide your weight by your height, then you divide that result by your height again.
The force of impact with the ground depends on the runner’s mass. The higher your BMI, the higher the forces involved, which means more impact and more stress on your joints, tendons, and bones.
If your BMI is above 25 kg/m², you can add lower-impact physical activity such as brisk walking, or non-weight-bearing endurance sports like cycling or swimming, to keep impact under control while improving cardio fitness. More than ever, gradual progression in running matters so your body adapts step by step. If you want to start running, these 10 tips to start running could be useful.
Running to Lose Weight
If you want to lose weight by running, you need variety in your training and a healthy diet. The goal is simple, burn more calories than you consume.
Some paces are also more effective than others for fat burning. When you run very easy in an aerobic endurance zone, your body tends to rely more on fat oxidation. For some people, that easy endurance zone can even mean fast walking, or alternating walk and run. Check out our advice on the best paces and workouts to lose weight.
You can also download the RunMotion Coach app. We created Weight Loss programs, available in Premium mode, combining a personalized running training plan with weekly nutrition guidance. Stay consistent and you will give yourself the best chance to succeed!