As joint injuries do, it is taking a long time to heal. A couple of weeks later, I was stretching my leg as straight as I could get it when it was nice and warm under the blankets, there was a distinct "click" and my knee has been (slowly and erratically) getting distinctly better since.
But, judging how it feels when I first get up in the morning, exercise the day before (particularly doing Heavy Hands(tm) or long walks) seems to be good for my wounded knee, even if complains at the time. Sitting on a stool is good, on a kneeling chair not so much.
Still, it does provide another reason to keep up with my exercises.
I have also been reading Good calories, bad calories. The point that the author makes that the second law of thermodynamics is an equation, not a causal statement, is a good and powerful one. (Or, more precisely, there is causation underlying it but the equals sign does not tell you where it is.) This refers to the weight = calories + exercise notion of weight loss. His point being that if what you eat affects your propensity for activity, then the causal relationship is not anywhere as simple as it is often portrayed. Particularly given the tendency for people to achieve stable weights. Your body's overall weight equilibrium is the result of a whole lot of cellular equilibriums: so if certain foods encourage energy and so activity while other foods encourage searching for further nutrition then your weight is not going to be a matter of mere calorie counting.
The burden of the book is that fat has been much maligned (Americans have been getting fatter while their intake of fat has been declining), but the news on sugar and simple carbohydrates is basically all bad (for both health and obesity). I was struck particularly by the story he tells of certain individuals with academic authority going on public crusades based on very limited or ambiguous evidence. Once something becomes "conventional wisdom" -- particularly if it becomes tied to government funding and media presumptions -- it can be very hard for counter evidence, no matter how powerful, to make headway. People have their "accepted and authoritative" frame of (cognitive) reference and they just go with it, with each iteration adding to its power as "accepted and authoritative".
Taking the book's broad advice, I have found that cutting back on the sugar and (particularly) simple carbs does seem lead to more energy and less weight. I am also cooking with butter (which tastes better anyway, and you do not use very much) and using the creamy yoghurt (which tastes better, has less sugar and not much more fat).
Heat oven to about 240oC. Grease baking dish with butter. Slice sweet potato relatively thinly. Place dollop of pesto on each slice. Bake for at least 20 minutes at at least 200oC. Remove and serve. (Yes, the pesto will go black, that's fine.)
I was particularly struck by the author's point about the second law of thermodynamics, as you get the same error being made in economics with causal misreadings of (aggregation) equations. Take the "Keynesian" equation of
GDP = C + G + I + X - MThis measures the results of actions by a mass of agents (like the cells in a body). It leads to Twin Deficit analysis where
(Gross Domestic Product = Private Consumption + Government Consumption + Investment + Exports - Imports).
(SP - Ip) + (M - X) = (Gp + TR - T)Or, to but it even more simply:
(Private Saving - Private Investment) + (Imports - Exports) = (Government purchase of goods and services + Transfers - Taxes).
Net Saving + Trade Balance = Budget BalanceThe basic idea behind the Twin Deficits hypothesis is that there will be a connection between the government budget surplus (T > Gp + TR) or deficit (T < Gp + TR) and the trade surplus (M < X) or deficit (M > X).
There are two problems with this. First, even in the equation there is the issue of (SP - Ip): if the actions of the government affect either private investment or saving, then there will be no simple connection between the budget balance and the trade balance. Changes in the budget balance could literally have any affect on the trade balance, depending on the response of private agents to both the way the deficit or surplus was generated and to the overall budget balance.
The terms in the equations are aggregations of billions of transactions by millions of agents. The agents drive what happens, not the aggregates. (Yet another iteration of the basic point of economics: incentives matter.)
Second, and extending the first point further, there is no causality implied in that equals sign. So, returning to the second law of thermodynamics as applied to nutrition, one could equally say weight - calories = exercise. Or weight - exercise = calories. There really is no causality implied in an equals sign (even when there is causation underlying an equation) when one is dealing with aggregates based on actions of a mass of smaller functioning things -- whether it is body cells or economic agents.
So, the next time people say or imply that weight is "just" a matter of calories and exercise, remember that an equals sign involving aggregates does not imply causality and your cells are massively more complex than that: just as how a government generates a budget balance matters, so how you get your calories matters. As your feelings of lethargy, energy, sleepiness, satiation and hunger will remind you.
ADDENDA: This post has been amended to make it clear that I am talking about equations involving aggregates.