His feet look like they lift weights.
No, that's fluid buildup. Look how deformed and swollen that is? That's the foot a diabetics gets as circulation and blood flow diminishes in the extremities like foot/calves and eyes.
Time for support socks. BTW, if feasible, you should wear support socks as much as you can, especially if you have a job where you are standing all day or on a long plane ride. Remember blood doesn't pump through your veins, only arteries. Blood moves through your veins via valves stimulated by muscle contraction.