Estimated read time: 4.52 minutes (about as long as it takes to convince yourself that one more long run won't hurt 🤔)

Hey Performance Nerds! Jonah here. 🤓

Most runners taper by cutting their fast workouts first. That's the last thing you should cut.

Bosquet analyzed 27 taper studies across endurance sports. Runners who kept intensity improved by roughly 3%. Runners who dropped it? Gains shrank or disappeared.

For a 3:00 marathoner, that's about 5 minutes of free speed. For a 4:30 marathoner, closer to 8.

Here's what you'll learn today:

(Augie has been tapering his squirrel-chase volume all winter. The sprint intensity? Still elite.)

Spring marathon season is here. This is the part of the cycle where patience pays more than fitness.

You did the work. The long runs, the track sessions, the strength work.

Now let the taper do its job. Cut the volume, keep the speed, and show up ready.

If you're heading into a taper right now, hit reply. Tell me your race and Augie and I'll check your taper plan.

-Jonah

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💡 See this week’s full Stryd training tip at the end of this newsletter.

Reduce volume 40-60%. Keep 100% of training intensity. Keep frequency at 80-100%.

That protocol produced roughly a 3% boost across endurance sports.

When athletes dropped intensity instead, the effect flipped. Gains shrank or disappeared.

Mujika, arguably the world's leading taper researcher, found exponential tapers outperform linear or step reductions. The biggest volume cut happens early, then levels off.

Neary et al. (2003) confirmed the sweet spot:

Too little rest doesn't clear fatigue. Too much removes the training signal.

In my own taper, I keep Wednesday's track session almost identical in race pace. I just cut the reps in half.

This isn't about strength. It's about how fast your muscles produce force.

When you stop giving your brain the intensity signal, it dials down neural drive to your fastest muscle fibers. Those fibers fire slower and weaker.

The speed of force production drops within the first week or two.

That's the difference between a crisp stride and "dull legs" on race morning. Your legs feel flat because they've lost their snap, not their endurance.

Those losses can reverse within 1 week of restored intensity. Fast to lose, fast to recover.

During a well-executed taper, fast-twitch fibers can actually improve. You don't just rest. You get faster.

Here's what that looks like for a 50 miles/week runner:

Your last quality session should land 4-5 days before race day. Think 4x400m at race pace or slightly faster.

Spilsbury et al. (2021) tested this in middle-distance runners. Intervals at 110% of race pace with 60% less volume improved times by 5.2 seconds over 1500m.

The group that kept race pace with only 30% volume reduction? No meaningful difference.

More rest, more speed. That's the pattern.

Two weeks works for nearly everyone. Mujika compared 50m swimmers to marathoners and found no significant differences in optimal taper length.

Your quality sessions during taper may feel harder than expected.

Your brain expects everything to feel effortless because volume is lower. But those sessions still demand full effort on a system clearing weeks of fatigue.

Feeling heavy during taper track sessions is normal. Cutting them is the mistake.

Mujika and Bob Bowman (Michael Phelps's coach) both say the same thing. Don't change the plan because of one bad session five days out.

Bottom line: The taper isn't about running less. It's about running less volume at the same speed.

Welcome to the prove you’re a nerd section. Each week, I ask a question about a common running science myth.

Answer correctly, and you’ll be entered into a weekly raffle to win a package of Jonah’s favorite supplements.

LT2 gets thrown around like it’s some mythical “redline” pace. But when you actually map it to race effort, things get more interesting.

The correct answer?
C. 10K to half marathon race pace (~35–90 minutes) 🧪 ✅

LT2 represents the highest intensity you can sustain while keeping lactate production and clearance in balance. For most trained runners, that lines up with efforts you can hold for roughly 40 to 90 minutes, not just a short all-out race or a full marathon.

Here’s how the votes shook out:
⬜️ A. Mile race pace (~4–8 minutes) ⚡ – 16
🟨 B. 5K race pace (~15–30 minutes) 🔥 – 52
🟩 C. 10K to half marathon race pace (~35–90 minutes) 🧪 – 187 ✅
⬜️ D. Marathon race pace (~2–4 hours) 🏁 – 17

A solid chunk went with 5K pace, which makes sense.

It feels like LT2 should be that “hard but controlled” effort you associate with a 5K. But most runners race a 5K above LT2, dipping into anaerobic contribution and accumulating lactate faster than they can clear it.

Marathon pace pulled a few votes too.

That’s the opposite mistake. Marathon pace sits well below LT2 for most runners, which is exactly why it’s sustainable for 2 to 4 hours when fueled properly.

Bottom line?
LT2 isn’t your max effort, and it’s not your easy pace. It’s the fastest pace you can hold without spiraling, which for most runners looks a lot like your 10K to half marathon gear.

Three weeks out from race day, I cut my track reps in half. 5x400 instead of 10x400. Same target power on every rep.

Weekly RSS dropped about 40%. That's expected. Fewer reps at the same pace means less total training stress on your system.

But the number I actually watched? Leg Spring Stiffness on each rep. LSS started climbing as the taper went on. My legs were losing the heaviness and getting springier. That's the signal you want.

Stryd's LSS captures how well your legs absorb and return force each stride. Think of it as a bounce test. Higher LSS means your legs are snapping back faster. During taper, you want two things: weekly RSS falling and LSS rising.

Why it matters:

Check your weekly RSS trend and your LSS on quality reps. Both tell the story.

👉 Try it on your next run