This is inappropriate please someone reported it because I can’t
I’m pretty sure this is true.
Answer:
Target Heart Rate
Explanation:
Target heart rate is generally expressed as a percentage (usually between 50 percent and 85 percent) of your maximum safe heart rate. The maximum rate is based on your age, as subtracted from 220. So for a 50-year-old, maximum heart rate is 220 minus 50, or 170 beats per minute.
The strength of your trunk or (core )including abdominal, low back, and postural muscles.