Heart Rate and Exercise
Your HEART is a muscular pump that beats your entire life — about 100,000 times a day. Each beat pushes blood around your body. HEART RATE = beats per minute (BPM). At rest, most adults sit around 60-80 BPM. During exercise, it can rise to 150 BPM or higher.
Why heart rate rises during exercise. Working muscles demand more OXYGEN. Oxygen rides on red blood cells from lungs to muscles. To deliver more, the heart pumps FASTER. That's why you breathe harder too — to bring in more oxygen for the blood to carry. The harder the exercise, the higher the heart rate.
A regular exerciser typically has a LOWER resting heart rate (50-60 BPM) than a non-exerciser (75-85 BPM). Why?
Find your resting heart rate. Sit quietly for a few minutes. Place two fingers (not thumb) on your wrist or neck. Count beats for 60 seconds. That's your resting heart rate. Most kids: 70-100 BPM (kids run a bit faster than adults). Track it weekly — it's a simple fitness gauge over time.
Heart Rate Experiment
Measure your resting heart rate (sit still for 3 minutes first). Now do 30 jumping jacks. Measure immediately. Wait 1 minute, measure again. Wait 5 more minutes, measure once more. Notice how it returns to resting. Faster recovery = better fitness.
Your heart is the most reliable, hard-working muscle in your body. Treat it well — exercise regularly, eat well, manage stress — and it'll keep you going for many decades.
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