Is Training Making You Slower?

Your easy pace is slower than it was two months ago. Workouts feel harder. You're doing more volume than you've ever done — so shouldn't you be getting faster?A listener wrote in with exactly that question, and it turned into a full episode. Coach TJ and Zoë unpack why feeling slower in a big block is usually the block working, not the block failing — and how to tell the difference when it isn't.The core idea: fitness and performance are not the same thing. Fitness is the physiological capacity you've built. Performance is how much of it you can access on a given day. Every training stimulus produces both a fitness response (slow, cumulative, quiet) and a fatigue response (fast, temporary, extremely loud). Fatigue is louder than fitness — you don't wake up feeling your mitochondrial density, but you absolutely feel Tuesday's workout on top of Sunday's long run.IN THIS EPISODE- Why aerobic base and durability are the two slowest adaptations in endurance sport — and why that means you can't train for just one race- The real sources of training fatigue: glycogen depletion, peripheral muscle fatigue, neuromuscular fatigue, connective tissue loading, and central/autonomic nervous system stress- Why comparing today's run to the same route two years ago on Strava is apples to oranges- Goodhart's Law in training: the moment easy pace becomes the metric you optimize, it stops being a useful proxy for fitness- Progress signals that actually mean something: same pace at lower RPE, same RPE over more vert, better output late in long runs, tolerating back-to-back long runs, and — the most underrated one — recovering faster from the same load- Can training make you less fit? The honest answer, plus why "worse at a 5K while training for a 100" isn't the same as losing fitness- Normal acute fatigue vs. functional overreaching vs. non-functional overreaching vs. actual overtraining syndrome — and why most athletes who think they're overtrained are under-recovered- The red-flag list: elevated easy RPE for days-to-weeks, repeated failure at previously manageable workouts, recovery that doesn't produce a rebound, sleep disruption, mood and motivation changes, recurrent illness, injury creep, menstrual cycle disruption- What TJ's biggest-ever build actually looked like: 15-hour weeks, multiple 100-mile weeks, four (sometimes five) long runs a week, and running slower than he ever hasALSO IN THIS EPISODE — HOT OR NOT- The Leadville 100: no qualifiers to enter, aggressive early cutoffs, and where the competitive incentives are drifting- Changing shoes mid-race (a caveated yes)- Sitting down at aid stations (a hard no, and the physiology behind it)- Listening to podcasts while racing (one yes, one very firm no)BETTER QUESTIONS THAN "AM I GETTING FASTER?"Am I tolerating more training? Am I recovering from it? Am I generally healthy and adequately fueled? Does performance return when fatigue comes down?Don't confuse a temporary inability to express fitness with the absence of it.- Zoë's UltraSignup article on Goodhart's Law: https://trailhead.ultrasignup.com/science-outdoors/data-for-runners/GET IN TOUCHQuestions for a future episode: [email protected] and community: https://microcosm-coaching.com