Anyone who runs knows the first few minutes can feel like a negotiation between your legs wanting to stop, your lungs feeling like they’re going to burst and your brain trying to convince itself that the next hill isn’t as steep as it appears.
But behind all that effort, your body is doing more than burning calories.
"Running affects most organ systems and can lead to multiple improvements in health," including better cardiovascular fitness, blood sugar regulation and mental well-being, says Dr. Chantal Nguyen, a board-certified, fellowship-trained sports medicine physiatrist with Stanford Health Care.
And you don’t have to be sprinting or training for a marathon to experience such benefits, as even short runs at a manageable pace can make a difference.
Here’s what happens when you run regularly, how long it takes to see improvements and how to build a routine your body can actually keep up with.
What does running do for your body? What are the health benefits of running?
Running offers many health advantages, but "the most prominent benefit is an improvement of the cardiorespiratory system," says Brad Schoenfeld, a professor of exercise science at Lehman College of the City University of New York.
Indeed, regular running can improve circulation, blood vessel function and stroke volume, which is the amount of blood pumped with each heartbeat. That last adaptation "allows the heart to pump blood more efficiently per heartbeat," Nguyen explains. Over time, this kind of activity can lower blood pressure, reduce the risk of heart disease and Type 2 diabetes and even extend longevity.
There are also benefits to how your heart and lungs work together, Schoenfeld says, since your lungs transfer oxygen into the bloodstream at the same time as your heart delivers it to working muscles. Running improves how you do both.
Working muscles also draw glucose from the bloodstream, and regular training helps them "respond more effectively to insulin," says Nguyen, which helps regulate blood sugar levels.
And because running increases calorie expenditure, it can also help with healthy weight management, says Schoenfeld.
Benefits extend to the brain as well, since "regular running can improve cognition and memory," says Nguyen. It can also support mental well-being, with research showing that walking or jogging can reduce anxiety and depressive symptoms.
Though predominantly positive, running doesn’t only affect the body in good ways. Each stride involves repeated impact on the lower body, which Schoenfeld says can be hard on joints, tendons and bones − especially when training exceeds what those tissues can tolerate as a result of pre-existing medical conditions.
Because of this, "all individuals should get clearance from their physician prior to beginning a running program if they have any health-related issues," says Schoenfeld.
How much running is needed to achieve benefits? Can I get in shape just by running?
Perhaps the best advantage of all, though, is that you don’t need to run fast or far to start seeing gains, as "many benefits can be achieved with even relatively modest durations," says Schoenfeld.
Nguyen agrees, noting that "starting at just 5-10 minutes of running per day is actually enough to decrease cardiovascular mortality," she says, "though greater benefits are seen with longer commitments."
For weekly targets, the Centers for Disease Control and Prevention recommends at least 150 minutes of moderate-intensity aerobic activity, 75 minutes of vigorous activity such as running or an equivalent combination − plus muscle-strengthening activities on two or more days.
While benefits increase with consistent application, some arrive sooner than others. For example, anxiety symptoms can ease after just one run, Nguyen says.
How to get the most out of your run
If running seems overwhelming, Schoenfeld suggests "progressing gradually," by starting with a routine you can repeat rather than one that leaves you feeling exhausted physically or mentally. Alternating walking with short jogging intervals can also help build endurance before adding longer or faster runs.
Nguyen also recommends limiting weekly mileage increases to no more than 10%, but to be mindful of adjusting that number to your fitness level and any recovery needs as tendon irritation, knee pain and bone stress injuries can all occur when training exceeds tissue tolerance.
"And remember that those who have had previous running injuries are predisposed to future injuries," she cautions.
Recovery matters, too. "Incorporate at least one rest day per week," Nguyen advises, as this will allow time to repair stressed tissues and replenish energy stores. And cycling or swimming between running days still offers aerobic exercise with less overall impact, says Schoenfeld.
Comfortable footwear matters as well, but Nguyen stresses that running mechanics are individualized and no single shoe choice works for everyone.
She also suggests staying hydrated and avoiding slick surfaces or running during the hottest parts of the day. Checking air quality before heading out is another useful precaution.
In the end, running affects the body in important and even life-extending ways, but the optimal effort and training volume, says Schoenfeld, "depends on an individual’s fitness level, goals and medical status."
This article originally appeared on USA TODAY: What running does for your body
