Using the Magic 180 Rule；
Here are the rules, taken from Maffetone’s Big Book of Endurance Training and Racing:
1）. Subtract your age from 180.
2）. Modify this number by selecting from among the following categories the one that best matches your fitness and health profile:
If you have or are recovering from a major illness (heart disease any operation or hospital stay, etc.) or are on any regular medication, subtract an additional 10.
If you are injured, have regressed in training or competition, get more than two colds or bouts of flu per year, have allergies or asthma, or if you have been inconsistent or are just getting back into training, subtract an additional 5.
If you have been training consistently (at least four times per week) for up to two years without any of the problems just mentioned, keep the number (180 – age) the same.
If you have been training for more than two years without any of the problems listed above, and have made progress in competition without injury, add 5.
The basic way to calculate your maximum heart rate；
运动能提高心肺功能， 减少和预防心血管疾病的发生（ cardiovascular respiratory endurance）
一般青壮年， 运动心率可达到最大心率的（intensive fitness) 60% --- 85%；
中老年人和 体弱者， 一般运动心率最好保持在最大心率的(lower or moderate fitness) 45%-- 65%；
1）. Calculation of Maximum Heart Rate
The easiest and best known method to calculate your maximum heart rate (HRmax) is to use the formula
HRmax = 220 - Age
2）. Check your resting heart rate (RHR)
3）. Determine the heart rate reserve (HRR)
HRR == MHR - RHR
4）. Calculate your training intensity (TI)
如果你是30岁， 你的运动心率可达到最大心率的60% -- 85%， 那么：
MHR = 220 - 30 = 190
如果你的休眠心率是：RHR = 68
则， 你的 heart rate reserve HRR=190 - 68 = 122
60%TI = (122 x 60%) + 68 = 141
85%TI = (122 x 85%) + 68 = 171
The “Karvonen formula” and its slightly more complex than the first two. Here's how it works:
Maximum heart rate (MHR) for both males and females is MHR = 211− (0.64 x your age).
Low Limit = (Maximum Heart Rate - Resting Heart Rate) x 0.6 + Resting Heart Rate
High Limit = (Maximum Heart Rate - Resting Heart Rate) x 0.7 + Resting Heart Rate
Low Limit = (Maximum Heart Rate - Resting Heart Rate) x 0.7 + Resting Heart Rate
High Limit = (Maximum Heart Rate - Resting Heart Rate) x 0.8 + Resting Heart Rate
Low Limit = (Maximum Heart Rate - Resting Heart Rate) x 0.8 + Resting Heart Rate
年龄随长， 要根据自身身体条件适当调整运动量和运动频率。。。多运动, 会运动， 安全运动！