The breakthrough occurred, a modest epiphany, on the Monday of our cycling holiday. It was the third day. We were cycling for a week on a few of the Croatian islands, the bikes and the cyclists taken by boat from one isle to the next.
The holiday had begun on the Saturday, where the Romantica was waiting for us at the harbour on the mainland of Croatia at Trogir. The cycling began on the Saturday too; there was no hanging around.
We had a quick lunch on the boat as it sailed the short distance from Trogir to Split, at which point the bikes were quickly taken off it by our guides, Bruno and Thoralf, and we headed out of the centre of Split for a 19km ride towards the nearby Marjan mountain. This was described as a gentle introduction, but I was quickly exhausted, finding the moderate hill out of the city more testing than I should have done.
Needless to say the views at the top were intoxicating: the sea, the nearby islands and the old town of Split underneath.
My wife and I had heard about this particular cycling excursion when we were on a short HF walking holiday on Dartmoor. HF (once known as the Holiday Fellowship) will celebrate its centenary next year. The organisation was established as a non-profit co-operative society to provide walks in spectacular scenery. It owns houses in some of the most stunning parts of the UK - two in the Lake District, one in Glencoe, many more scattered around the country - always with vast gardens looking out towards mesmerising scenery.
We meet up with friends a few times a year at different HF houses in the UK for long weekends and guided walks. HF now offers a huge range of walking and activity holidays in Europe, based on the same principles as its UK holidays, and we'd decided to take the opportunity to see Croatia from two wheels.
That evening, Bruno and Thoralf took us for a walk around Split. The cathedral and the squares were beautifully lit, like near-empty sets preparing to stage a Shakespeare play.
There were 30 of us in the group, a mixture of Germans, Australians, Americans, Spanish and English. Reassuringly the ages varied from early seventies to much younger, although my complacency later turned out to be misjudged.
The following day we cycled on the mainland from Split, beginning with a gentle, flat, relatively easy ride along the valley of the Cetina river. Suddenly we turned left and began a steep climb for nearly five kilometres.
One of the Australians in his seventies sped past me, advising me that the effort must come from the legs alone. As I was wheezing in the manner of an asthmatic elephant at the time, I suddenly realised generational gaps were meaningless.
However, there was a reward for all of us when the peak was reached, with dazzling views of mountains on both sides and a small cafe serving good coffee.
The talk during the coffee was also inspiring. Quite a lot of our group cycled at weekends; the two in their seventies half-joked that when they got old they would avoid the mountains and cycle around the Netherlands.
On our return the boat took off for Brac island, a 40-minute journey from the mainland. The following morning I awoke feeling healthier than for a long time, even after a few glasses of the local wine at a tiny bar at the small port the night before.
I was enjoying the clear air and exercise, away from the fumes of London. The world of politics, Twitter and the frustrated ambition of Westminster matter little when you are trying to cycle up a mountain.
On the Monday morning we cycled to the other side of the island to Bol, where lay a beach and our first swimming opportunity. For the first hour we had to navigate a steep hill, and halfway up the unrelenting ascent I was starting to get breathlessly irritated by the ordeal.
I listen to music when I cycle or run in the UK so I put on some headphones, fantasised I was Mick Jagger in his prime and rocked upwards.
At one point one of the German women overtook me. Hearing my sharp intakes of breath, she asked: "Stephen, are you singing ... or are you ill?" I told her I was singing, but in truth I felt ill.
Shortly afterwards, though, my mild epiphany took place. I got the cyclist's high, the endorphin hit normally associated with running.
By the end of the climb I had even begun to like the hill - and when we arrived at Bol the coffee tasted better than ever, the swim was utterly reviving.
After that, each day I awoke looking forward to the hill climbs. I never thought I would write that last sentence.
Boat and bikes are a good combination for island hopping. Our boat appeared as if from nowhere at the harbour in Bol, and Bruno and Thoralf lifted the bikes on to the vessel and into the arms of someone on the deck.
We were off next to Mljet, a small island with a population of 400, where we rode around a lake to a lunch spot, swam and cycled back to the boat and on to the much bigger island of Korcula.
Bruno and Thoralf warned of a long uphill the following day, very steep for 5km and then another climb later, both more demanding than any ride so far.
Thankfully they also offered what they called Plan B, a short ride along the coast then the boat to Korcula's main port. I chose Plan B. But after my epiphany I still wanted another hill, a whiff of Plan A.
Fortunately, on the next island of Hvar we had a steep climb for 10km before a joyful descent.
By the end of the week I was fitter than I had been for a long time, and had caught more than a glimpse of these captivating Adriatic islands.