(Health care for the elderly) What is the appropriate amount of exercise for a healthy 70-year-old to make his heart rate normal after exercise? How should I calculate it?

1) Standard for measuring modern people's health 1) Physical health can be measured by "five fasts": ① Eating fast: it doesn't mean eating the meal in just a few minutes, but it means having a good appetite when eating, not being picky about food, and being able to finish a meal at a normal speed, indicating that the internal organs function normally. (2) Walking fast: refers to walking freely and agilely, indicating that it has good musculoskeletal ability and is full of energy. (3) Fast speech: It means that the language is correct and fluent, and you can make a complicated thing clear in two or three minutes, which shows that your mind is agile and your heart and lung function is normal. (4) Sleep fast: it means that you can fall asleep quickly and sleep well after going to bed. After waking up, you are full of energy and clear-headed, indicating that the central nervous system is running well and there is no interference from pathological information. ⑤ Faster defecation: once you have a feeling of defecation, you can defecate quickly, 1 ~ 2 times a day, and urinate 5 ~ 6 times, indicating that the stomach, intestine and kidney function are good. 2) Mental health can be measured by "three good": ① Good personality: stable mood, gentle temperament, strong will, rich feelings and open-minded optimism. (2) Good social skills: refers to the insight into the objective reality of the problem, good self-control ability and adaptability to the complex social environment. ③ Good interpersonal relationship: it means helping others, being kind to others and having a good relationship with others. (2) Human health needs four balances.