Browse evidence-based analysis of health-related claims and assertions
Sprint workouts might boost your muscle energy factories way faster per minute than other types of exercise — about 2-4 times more efficiently than harder or longer workouts, especially if you're just starting out or somewhat active.
For people who aren't super fit to start with, different types of workouts—like steady cardio, intense interval training, and short sprints—boost the energy powerhouses in their muscles by about the same amount, around 23–27%.
Doing light, steady exercise like walking or slow cycling doesn’t seem to change blood sugar levels much in healthy adults who don’t usually exercise.
Even light exercise can be good for your heart and fitness, but the harder you work—within a low-intensity range—the more you’ll improve. There’s no ‘too easy’ when it comes to getting some benefit from light workouts.
Doing light, steady exercise like walking or slow cycling can slightly improve heart health in inactive adults — lowering blood pressure and bad cholesterol while raising good cholesterol. Even small changes add up to lower heart disease risk over time.
Doing light, steady exercise like walking or slow cycling can help your body use oxygen better during everyday activities and may lower your risk of heart problems over time.
Doing light, steady exercise like brisk walking regularly can significantly boost your heart and lung fitness—even if you're just starting out. That kind of improvement could lower your risk of dying from any cause by over 10%.
When young guys with obesity do intense interval running, they burn more total calories than when they do steady, moderate running—even if the workout burns the same calories—because their bodies keep burning extra calories afterward.
For young guys with obesity, doing short bursts of intense running burns 300 calories faster than jogging steadily — about 8 minutes less effort for the same result.
When young guys with obesity do intense burst running, their bodies burn a bigger share of fat in the hours after the workout compared to when they do steady, moderate jogging—even if both workouts burn the same total calories.
When young guys with obesity do intense burst running, their bodies burn more fat in the half-hour after the workout than when they jog steadily — even if both workouts burn the same number of calories.
When young guys with obesity do a tough workout with short bursts of fast running, their bodies burn more extra calories after the workout than if they jog steadily for the same total energy cost.
If a fit guy burns more carbs during a tough workout, he's likely to burn more fat afterward while recovering.
When fit guys do intense circuit workouts, their bodies burn way more carbs during the workout compared to when they do steady, moderate exercise — like 33 vs 13 carbs per minute for every kilo they weigh.
After tough workouts like HIIT or circuit training, fit guys burn fat faster in the hour after exercise compared to easier, steady workouts—even though they burn less fat during the actual workout.
After tough workouts like sprint intervals or fast-paced circuit training, fit guys burn more carbs in the hour after exercise compared to easier, steady workouts — which might mean their bodies are working harder to refill energy stores.
For fit guys, a tough but short workout leads to burning more calories after exercise compared to a longer, easier workout—even if both burn the same total calories. That’s because intense workouts keep your metabolism revved up longer.
Doing intense bursts of exercise with rest in between can keep your body burning more calories for up to a whole day after your workout.
Doing super intense workouts in short bursts burns more calories in less time than going easy on the exercise.
When you do light, steady exercise like walking, your body burns more fat compared to carbs than when you're going harder, like running.
Doing light, steady exercise—like a brisk walk—can boost the energy powerhouses in your muscles.
Doing light, steady exercise—like a brisk walk or slow jog—for 30 to 60 minutes, where your heart is pumping at 60–70% of its max, helps improve your endurance and how well your body uses oxygen.
This idea says that a smarter math method can help scientists better tell when a workout doesn’t work — not just when they don’t have enough proof either way.
If you keep the resistance the same at different arm angles during cable curls, you can better compare how muscle stretch affects growth, without other forces messing up the results.