Mixed fortunes last month. On the face of it I lost a further 2.7kg (5.95lbs) in May, but the headline figure masks a lot of volatility over the month. Most of the volatility was within the usual tolerances for daily fluctuations in weight. I am well short of the targets I set for myself in January, but the trend was clearly down and I’m feeling good about myself.

My hypothesis about the weight fluctuation is that my metabolism has found an equilibrium point and I’m likely to stay in this weight range unless I make a change to the dynamic of my system. Picking up the running is that change. Also, and at the risk of offering too much information, skin elasticity diminishes with age, so, although I have lost a lot of weight, I need to ‘fight the flab’ and lose the residual loose skin around my middle. A rowing machine would help, as would some dumbbells, but I started doing sit-ups/crunches today. It wasn’t easy, but you’ve got to start somewhere.

The better news is that my return to running is progressing. I had a slight setback when I had a pull in my calf, which I rested completely until it had healed: I don’t want to incur any significant injury, and injuries are more likely, and will take longer to heal, at my age. However, on each of this past Saturday, Sunday and Tuesday I ran 4.2km (2.6 miles). The Tuesday run was hard on the thighs, though, and I walked a little of the final segment. Twenty years ago, a day to rest was fine; now that I’m 62, I need a bit longer. Lesson learned. But what I am now reasonably confident of is that by the end of June I should have managed at least one 5km run and hopefully more than that.

One of the key things I’m learning from all of this is to take a systems thinking approach. Although there are some short-term cause and effect aspects of dieting and exercise, over the longer term it pays to take a systems approach and look at how a set of changes work together to change equilibrium points, creating ‘new normals’. Even though my progress is slower than I expected in January, that’s largely because my analysis in January wasn’t focused enough on the body as a system. That’s why I’m comfortable now with a slower rate of change.