Or words to that effect. It was not by accident that I scheduled my annual physical for the week after returning from the UK. This morning I found that in addition to losing three pounds of (mostly) abdominal fat, my resting heart rate was 4 beats lower, and blood pressure registered a very nice 107/69. Later this week I'll get the results of blood and urine tests, which I won't share unless there is a huge adverse surprise. But I suspect my cholesterol will also decrease.
As those (like Lyn) who saw me eschew the greens (and especially the various colors of bell peppers and cucumbers) and ingest an unbalanced number of steak and ale pies, can attest, my eating habits for the last month left a lot to be desired. However, at no time did I feel tired or run-down in an unhealthy sort of way. But that was only short-term, I am now back to eating fruits and vegetables. I don't think I can hold down my weight more than another month, then it will creep back to normal (hopefully no more than 150).
I now have some heart-rate statistics from the trip. Surprisingly, even on the most strenuous days, the average heart rate did not exceed 113 (67% of max). But when it went up, it was in the 90-95% range. Conclusion: you don't have to spend enormous amounts of time in Zone 4 or 5, but you do have to spend multiple short bouts there in order to achieve a training effect. Of course, I already knew that from Chris Carmichael and Sally Edwards.