Son,

I was out walking again today. My brain almost refuses to accept the age of my body. “Come on,” the brain says, ” if you had not been so lazy you would not be in this mess.” My body argues in return, “You are Management, production has lagged because of inept management.” I feel like an arbitrator, caught between the union laborer and a feisty boss. We have to find a compromise. I think I stumbled on the solution while arbitrating on my daily walk. I call it the ‘age factor.’

The Age Factor:

First I had to establish a baseline to measure from. So I thought back to when I was thirty years old – what were my exercise expectations at that time? I remember thinking that walking was anything over 12 minutes a mile, jogging was 8 to 12 minutes a mile, anything under 8 minutes was flat out running. 5 minutes a mile and you were in the Olympics – but that was never a problem for me. So how do we factor in age?

I used age 35 as the break point. So under age 35 and 8 – 12 minutes is a factor of 1. After age 35 I add a factor of 0.01 for each year of age. So at age 40 I would multiply the 8 minute rule by 1.05, adding 0.01 for each of five years from 35 to 40. At age 40 the break point from jogging to running is 8.4 minutes per mile.

Aging is an exponential degeneration of physical ability. So this must be considered. At age 50 the factor increases to 0.02 per year. So let’s say a person jogged 8 minute miles at age 30. At age 57 this person would derive the same benefit by jogging 10.32 minutes per mile. That is to say 0.15 for the fifteen years from age 35 to 50, another 0.14 for the 7 years to age 57 for an age factor of 1.29 * 8 = 10.32 minutes per mile.

The Sedentary Factor:

My brain and my body are coming to an understanding. As complicated as this might sound – it gets worse. The above example assumes a person has stayed moderately active through the years. So we have to factor in sedentary life. Add 0.03 to the age factor for every year you have been sedentary. Five years of no exercise – add 0.15. So in the example of the 57 year old above, assuming he had been sedentary for five years, his age factor would be adjusted to 1.44 ((1.29 + 0.15) * 8 = 11.52) as fast jogging. Remember the outer limit of jogging at age 30 was 12 minutes. With this in mind our 57 year old sedentary man would enter the world of jogging at 1.44 * 12 – or at 17.28 minutes per mile. For every month of regular moderate exercise the factor can be reduced by the sedentary factor of 0.03. This will allow for improving health over time.

The Weight Factor:

Our 57 year old man is carrying a pack that he did not possess at age 30. It weighs about forty pounds and is draped around his body. This extra weight cannot be ignored when setting goals for a healthy program. I don’t care much for height/weight charts but they can serve as a relative baseline for our exercise program. To adjust our age factor according to weight we add 0.01 for the first 10% over the recommended weight, 0.02 for the second 10%, 0.03 for the third 10% and incrementally up the scale. If our 57 year old man’s height/weight chart is at 160 pounds, and he weighs 200, then he gets to add 0.10 + 0.02. Now the man, age 57, sedentary for five years, and 25% overweight has an age factor of (age + sedentary life + weight.) It breaks down like this 1 (baseline) + 0.29 (age) + 0.15 (sedentary life) + 0.03 (weight) times the baseline slow jog of 12 minutes per mile and his jogging target is 17.64 minutes per mile. What was once a nice walk at 15 minutes per mile becomes 15 times 1.47, or 22.5 minutes per mile as a good target for beginning exercise. Again – as with the sedentary factor, when we drop weight we drop the factor accordingly.

Anyone who is aging, sedentary, and overweight and is considering an exercise program should probably go see their family physician. Get a good physical. Make sure there are no underlying health issues that will subvert the effort. Your physician can also give you some guidelines on diet and nutrition. Don’t be embarrassed to go to the local YMCA and hire a personal trainer for the start-up exercise program. Be careful.

I continue to develop these formulas. It strikes me that there is a break point – and I am not sure where it is. But consider this, if your factor comes up a powerful 5, think about walking backwards.

Dad