September 4, 2023
“By understanding muscle as the key to longevity and taking action to rebalance the effects of losing and gaining muscle, you can slow the process of aging,” contends physician Lyon in her sturdy debut. She recommends eating a protein-rich diet to maintain muscle mass, explaining that consuming at least 30mg of protein during a meal is usually enough to trigger the process by which the body turns amino acids from protein-rich foods into skeletal muscle. Resistance training is crucial for long-term health, according to Lyon, because it prompts muscle contraction that “stimulates the uptake of glucose” from the bloodstream “without any need for insulin’s assistance,” reducing the chances of developing health conditions related to decreased insulin sensitivity, such as type 2 diabetes. Lyon’s tough love approach will help readers overcome mental hurdles (“If you don’t want to quit at least once, you’re not working hard enough”), and the guidance is pragmatic, as when she describes how to combine chest presses, reverse crunches, side planks, and other exercises to create a well-rounded workout while acknowledging that the time commitments she recommends might not be feasible for some people’s schedules. Advising readers to do their best given their constraints, Lyon writes, “There is one slam-dunk way to exercise wrong: don’t do it at all.” The result is an encouraging manual on staying fit in old age.