THREE KEY FACTS: Interval training can be effective, but must be adjusted to individual needs. People without medical issues can start a light-to-moderate exercise programme after a doctor’s clearance. Regular exercise can cut your risk of heart disease by a third, regardless of age.
I woke at 5am on my first day in Shanghai and spent most of the next hour trying fruitlessly to get back to sleep. Because I couldn’t think of anything else to do, I went to the hotel gym. I thought of myself as a fit person, presumably because I had been one once .
This was my first mistake. I took the elevator down to the gym, walking in shortly before 6am. I hadn’t anticipated exercising on the trip, so I was forced to dress ludicrously, in togs and an old T-shirt.
Embarrassingly, five appropriately dressed men were already there..
Health
Shanghai gym visit turns into health scare for midlife Kiwi traveller

I woke at 5am in Shanghai and couldn't get back to sleep, so I went to the gym.