Should You Train to Failure? What 4 Coaches Actually Do

Short answer: it depends which "failure" you mean. Some evidence-based coaches push individual sets to true, can't-move-the-bar failure. Others deliberately build volume while stopping just short of it. Both camps can point to real results — the disagreement is about which sets, not whether effort matters at all.

What the evidence says

Nobody serious argues that low effort builds muscle — that part's settled, and it's really just progressive overload's sibling principle. The live question is narrower and more interesting: once you're already training hard, does the last mile to true failure add anything extra, or does it just add fatigue you have to recover from before the next session?

Jeff Nippard ran into this question directly. Working with only 1–2 sets available per exercise, he noticed a "focus effect" — with fewer sets on the clock, every single one got pushed to genuine failure, no holding back. He points to Robinson et al. (2023) as backing: proximity to failure, not raw set count, appears to be the bigger hypertrophy driver. His current rule of thumb reflects it — cutting calls for low volume and high intensity (fewer, harder sets), while bulking still rewards blasting one muscle at a time with real volume.

Sydney Cummings Houdyshell takes the most literal version of "train to failure": pick the heaviest weight you can move with good form and still hit failure by the set's end, because in her words, "failure is the stimulus for growth." Her "great eight" rule — eight genuinely hard, controlled reps beats a sloppy pile of easy ones — is the same idea applied specifically to core and glute work, muscles she says people let off the hook far too often.

Renaissance Periodization's Dr. Mike Israetel runs a more technical middle path. In a session he designed for CrossFit athlete Mat Fraser, he used "myo-rep" clusters — 25 total reps broken into mini-sets of 3 to 5, with only 5–10 seconds of rest between them — specifically to rack up high mechanical-tension volume without ever taking an individual mini-set to true failure. The logic: you get most of the growth signal from proximity to failure across the whole cluster, with less of the systemic fatigue that comes from grinding out a genuine last rep on every single set.

HASfit's Coach Kozak sits closer to the moderate end for a home-training audience: pick a weight where the last two or three reps of a set are tough, then reassess after the first round of each block. Close to the edge, without necessarily stepping over it every time.

Where the coaches disagree

• Push every available set to true failure (Nippard, in his reduced-volume protocol; Houdyshell, as a standing rule): fewer sets, maximum proximity to failure on each one.
• Get close, but stop short via clusters or technique (Israetel's myo-rep approach): accumulate the same tension over more total reps, spread thinner, to reduce the fatigue bill.
• Stay near the top of hard, without chasing failure specifically (Coach Kozak): a sustainable, less punishing default for people training frequently at home.

The common thread underneath all three: intensity — real, near-maximal effort — is doing the work. What splits them is how much of the recovery cost of true failure is worth paying for the last bit of stimulus it buys you. That's a genuinely open question, and it plausibly has a different answer for a competitive lifter with unlimited recovery time than it does for someone training around a full-time job.

Run your own experiment

Two weeks each, on an accessory lift you don't mind experimenting with — not your heaviest compound movement:

1. Weeks 1–2 — true failure. Every working set goes to the point where good form breaks down or the weight stops moving. Log soreness the next day and whether you actually recovered in time for your next session on that muscle.
2. Weeks 3–4 — myo-rep style. Same total rep target, split into mini-sets of 3–5 reps with 5–10 seconds rest, stopping each mini-set one or two reps short of failure.
3. Compare on three things, not just soreness: did strength or reps trend up either way? Did one approach wreck your motivation to show up for the next session? Which one did you actually finish both weeks of without skipping a day?

The "correct" answer here is legitimately the one you'll repeat. A theoretically superior protocol you quit in week two loses to a slightly-less-optimal one you're still doing in month three.

FAQ

What does "RIR" mean? Reps in reserve — a rough estimate of how many more reps you could have done before failure. 0 RIR means true failure; 2–3 RIR means a couple of reps left in the tank. It's the shorthand most of the coaches above use to describe where they're stopping.

Is training to failure bad for beginners? Not bad, exactly, but rarely necessary — beginners tend to grow from almost any real effort, and learning good form under fatigue is a skill in itself. Most coaches in this range would suggest building that skill before chasing true failure often.

Do I need to hit failure on every set, or just the last one? Most of the coaches above who use failure at all reserve it for the final set of an exercise, not every warm-up or working set before it — going all-out too early just eats into the sets that follow.

How do I actually know if I hit true failure? It's the rep where your form breaks down or the bar stops moving despite real effort — not the rep where it just started feeling hard. If you're unsure, you're probably not there yet.

---

Four coaches, three different answers, and a tribe about to start arguing about it too — join early at imbatribe.com.