Near the culmination of a bicycling season where you finished second five times and third once in your first 14 races, what could possibly be better than winning the 15th? How about winning while setting a personal record by 33 seconds on a course you had done a number of times in your 40s.

When you are 55 years old.While I knew I could still win hilly age-categorized races, I thought my days of setting PRs in time trials were over. To say I was exhilarated, elated, ecstatic, or any other word that suggests a trip to the enchanted state of Euphoria would be accurate. And upon my return, I was like a junkie coming off the really good stuff. I just had to get that high again.Since success leaves clues, I reviewed my dietary and training logs closely and learned a lot. Here's the part worth sharing with you: I'm still losing the war - just not as badly as before.It's a war we all must wage sometime in middle age.Our opponent is what doctors define as sarcopenia, the age-related loss of muscle mass that creates a loss of strength and functionality. It begins sometime after age 40 for those physically fit, as early as age 30 for those who aren't, accelerates rapidly around age 75, and causes many people to lose up to 30 percent of their muscle mass by age 80.No matter what you do, you lose muscle mass eventually. But you can delay and sometimes even partially reverse the process if you ingest sufficient protein, get an ample amount of rest, and continually experiment with your type and intensity of exercise.Exercise experimentation, I believe, led to the PR in that time trial, and -ironically enough - the initial experimentation did not occur on the bicycle. It took place in the weight room.As you age, you first lose fast-twitch muscle fibers - the ones that allow you to move explosively and forcefully - but not because of a problem with those fibers initially. The fast-twitch motor neurons that allow your brain to activate the fast-twitch muscles age and die. No activation means no movement, which leads to atrophy and often muscle fiber death.When the fast-twitch muscle fibers don't die, it's because slow-twitch motor neurons "save" them in a process called motor unit remodeling. But the remodeling changes the way the fast-twitch muscle fibers function. They lose much of their ability to contract quickly and forcefully, but develop more endurance, meaning they function more like slow-twitch muscle fibers than the fast-twitch muscle fibers they once were.That's what it felt like was happening to me on the bike. At an 80 to 85 percent effort, I had as much endurance as ever, but my ability to make a quick burst had diminished. And since I know about sarcopenia, I felt this change was part of that process.But then it occurred to me that some part of the change - possibly even a large part of it - might be my own doing.At age 41, a complicated fracture of my funny bone kept me from "heavy" lifting in the weight room as well as bicycle racing. In the 10-week period where all my workouts were performed on an indoor stationary bicycle, I lost 10 pounds, much of it upper-body muscle not needed for bicycle racing.Because of this loss, I almost won a very hilly high-level race the first time I raced again - even though I had done no specific hill training beforehand. After that, I had no desire to regain the lost muscle, but knew I needed to retain some strength. As a result, I focused on lifting lighter weights for higher repetitions.That pattern served me well - until the last three years or so when sarcopenia started sucking muscle from my frame. The low-weight, high-rep work, I imagine, wasn't providing enough stimulation to keep the fast-twitch muscle fibers from atrophying.So I began to lift "heavy" weights again.Bear in mind that heavy is a relative term. Heavy for me now is about 65 percent of what it was back in my late 20s when I was about 25 pounds heavier.That reduction in barbell weight depressed me to no end - until I began to sense something, almost like an awakening. No, my fast-twitch muscles weren't firing as quickly as they did in my 20s. No, my bike sprinting wasn't as fast as it had been in my prime.But I knew I was producing more power to the pedals than a year or two or three ago. I knew I was faster on the bike because of it.And more importantly I was feeling good. Not just on the bike. All of the time.Little things like cutting the grass or moving the refrigerator just didn't seem to take as much effort. I was waking up refreshed and ready to go most mornings instead of still tired and ready to curse the alarm clock.I share my good fortune with you because you too may find an increase in anaerobic exercise intensity effectively combats sarcopenia and creates an increase in vitality.