I have worse news. The wear and tear isn’t just a matter of insufficient pillow hours. My body is also slowly capitulating to parenting’s physical grind. The specifics of how, why, and where of my nagging injuries has varied as the kids have grown up, but the early years are a particularly tough time. Think of infants and toddlers like medicine balls. Except kids are: 1) less dense, 2) more mobile, and 3) heavier (eventually). Most critically, unlike exercise equipment, when I lift my kids, I’m usually lifting them for a practical purpose, like maneuvering them through a car door and into their car seats—which is impossible to do without twisting, straining, and torquing my back like an arthritic, uncoordinated Gumby.

Don’t think that I’m sandbagging it here. I’m in decent shape. I run between 15 and 25 miles most weeks (at around 7:15 splits). I’ve been a bike commuter for nearly a decade. I do pretty regular core workouts. I’m no Olympian, but my BMI and blood pressure are two of the only things that I don’t worry about as a dad…

Parenting exhaustion is unflinchingly certain. It’s right there with death and taxes. It’s already out there, waiting for you just outside of some far-off hospital maternity ward. Unless you can afford a 24-hour au pair, you can’t dodge this. No matter when you have kids, they will exhaust you. The sleep deprivation will screw you up. What’s more, your muscles are less injury-prone now than they will be. Your skeleton has less mileage on it. Whenever you have kids, they will leave you with lifelong physical scars (you too, dads).