Fitness
How do fitness trackers estimate calorie burn and how accurate is it
Trackers estimate calories from heart rate, motion, and your stats, but validation studies show errors of 27 to 93 percent. Here is what
Cardio
Rive News Cardio: heart and lung fitness explained. Running, conditioning, and endurance science without the hype.
Fitness
How long it takes to lose fitness when you stop training
Cardio fitness fades within 2 weeks of no training, with VO2 max down 6 percent at week 4 and 25 percent at week 11, while strength holds
Fitness
Why do I get out of breath so fast when running?
Getting winded fast on a run means your muscles need more oxygen than your heart and lungs can deliver. Here is how VO2 max and training
Fitness
Why Am I Not Losing Weight Despite Exercising?
A Pennington trial found exercisers ate back 91 to 124 calories a day. Here is why the scale stalls despite regular workouts, and what