I have a husband who has a little known disease he has named Mall Knees.
This is a disease that manifests itself by causing dull aching calves and knees primarily in the male of the human species. A two-hour foray through Home Depot tool departments does not cause Mall Knees, especially the area surrounding table saws, skill saws, reciprocating saws and band saws. Even chop saws. The viewing of limitless automobiles at car dealerships does not cause Mall Knees.
The exploration of the back aisles of Outdoor World, plundering perusal of sports equipment and clothing, canoes and associated paraphernalia used to keep one dry while under water, does not cause Mall Knees. Unlimited wandering for days among sleek and/or rugged motorcycles, helmets, gloves, leathers, riding boots and chaps, maps and trail guides, amazingly, do not cause Mall Knees.
The direct association with tractors, it seems, also does not cause Mall Knees. Actually, quite the opposite effect. I've noticed a long-acting revelation of accelerating stimulation to occur, and have myself witnessed marathon days of tractor ogling with no sign of Mall Knees making an appearance. Motor homes and other RV types seem to have a similar effect. Ditto marina sweeps where boats are apt to hang out.
However, after thirty minutes of wandering calmly through a mall, the victim carrying nothing heavier than a Starbucks coffee, the pain begins somewhere around the ankle. It's not really very bad at that point. But breathe the air inside a department store's (female) clothing department and excruciating cramps will occur beginning from under the kneecaps and running down the gastrocnemius muscles. I'm talking cramps very similar to those of a dehydrated marathon runner lacking potassium, lacking electrolytes. At that point, the victim must be taken home at once, his legs rubbed and he (remember the victim is always a he) is forced into bedrest with TV.
I've researched this, people. That's how I know. I have a male person I use as standard bearer for their percentage of the human population. I've seen this happen before my very eyes.