I'm 63 and have been riding/running for almost 25 years. The "wisdom" seems to say that my Max heart rate should be 220 minus 63 = 157. When I really push myself on the road bike [as in an HR test], my HR goes up to 168 or 169. On just a normal ride, my HR stays around 145 to 150.
During our heavy rains a few weeks ago, I got on a treadmill for 20 minues or so, and my HR went up to a sustained 178 and flirted with 179.
Anyone have any comments? Surely, I'm not doing damage to my heart.