Everyone wants to lose weight or at least keep it the same. Just look at the web, magazines, newspapers, etc and there are more ways to part with a person's cash for the promise of weight loss than Carter has attack rabbits.
The recommended approach is usually to "eat right and exercise regularly".
If you want to "eat right" go read the entries in my blog called "Disgusting Food" (coming whenever) on how to turn disgusting green and yellow vegetables into something yummy, ...that I often rename to avoid memories of "out of the can" cooking. :-(. "Good Food" actually is good but it takes a bit to prepare it.
For that "exercise" thing,
what they don't tell a person is that "more is counterproductive"!
at age 60
Lose Weight/ Burn Fat
60% - 70%
Now, they never show you those heart rate values! If a person's HR exceeds 112, doing exercise at age 60, that person isn't likely to lose much weight! Instead, they will work until they run out of ready fuel and then just stop "too tired" and very hungry!
Now, think about how fast a bicyclist will go at a HR of 112. No, not coasting down a hill, but UP that hill! I don't know about you, but to go UP hill is usually a lot higher than 112!
So, if a person is over age 40 and they want to !!FAIL!!at completing STP in one day, it's easy:
STP is 200 miles with about 4000' of elevation gain. In 16 hours represents about 14 mph with no stops and going uphill a bit of the time. I suspect a person isn't going to do well at a heart rate of 112!