Inside The OPEX Method Week 5: Anaerobic Training, “Pain,” And When It Actually Makes Sense

If you coach long enough, you eventually meet that client who wants to “go hard or go home” every session. Week 5 of the OPEX Method is all about that world of anaerobic training, what OPEX calls “pain” or “unsustainable” work.

The twist: most people should almost never do it, and most coaches misuse it when they try.

Week 5 highlights: OPEX Pain

This recap breaks down how OPEX teaches anaerobic training, how it fits into the larger energy systems model, why it is so demanding, and when it actually makes sense to use it in a real coaching practice.

The OPEX Energy Systems Model, In Simple Terms

Two weeks before this module, the coaches in the cohort built a simple energy systems training (EST) model with three pieces:

• CP / ATP work (short, explosive, high power)

• Aerobic work (sustainable, oxygen-supported)

• Anaerobic work (glycolytic, very intense, unsustainable)

All three systems run together in the body, but one will be dominant based on what you ask the client to do. The OPEX approach uses two simple cues to understand which system you are hitting:

• How the work feels

• How long it takes to recover between efforts

ATP is the “energy currency” of the body. If you drain it fast, you need more rest. If you spend it slowly, you can keep going. That simple idea is how they separate aerobic from anaerobic in practice.

Here is a quick comparison based on the model coaches worked from:

Energy systemTypical work timeTypical rest timeHow it feelsCP / ATP1 to 10 seconds60 to 300 secondsVery explosive, not much “burn”Aerobic (tough)20 to 60 secondsAbout 1:1 with workHard but steady, repeatableAnaerobic10 to 120 secondsAbout 10 to 20x workVery painful, very non-repeatable

That ratio is the big eye-opener.

If a client does 10 seconds of true anaerobic work, they might need 150 seconds of rest to regain the ATP they spent.

Compare that to a 30 second tough aerobic piece, where rest might also be 30 seconds. Same work time, totally different system.

Once coaches see that difference in rest, it is much easier to feel when a client is actually in anaerobic territory and when the session has just turned into hard aerobic work or random suffering.

What Counts As True Anaerobic Training?

OPEX calls anaerobic sessions “pain” or “unsustainable” for a reason. They are powerful, very stressful, and cannot be repeated many times in a row without long rest.

In practice, true anaerobic work looks like:

• Short to mid-length effort (often 10 to 60 seconds, sometimes up to 2 minutes)

• Very high power output relative to the athlete’s capacity

• Long rest periods, roughly 10 to 20 times the work time

• A clear drop in ability if rest is cut short

A big point in the lecture was this: a lot of research that talks about “high intensity training” is actually describing tough aerobic work, not anaerobic work.

The classic example is the Tabata protocol: 20 seconds on, 10 seconds off, for 8 rounds or more.

It is absolutely high intensity, but it is not high intensity anaerobic in the way OPEX defines it. The rest is far too short for the athlete to reproduce real anaerobic power over all the rounds.

What happens instead:

• The first few rounds might feel anaerobic in intent

• The body cannot rebuild ATP fast enough

• The system shifts to more aerobic support to keep you alive

• Output drops and it turns into a “just survive it” session

You are no longer training the anaerobic system in a targeted way. You are just teaching the body to suffer through fatigue.

OPEX’s version of a true anaerobic interval looks more like:

10 seconds all out on an Assault Bike, then 150 seconds of rest.

Simple, ugly, and very effective when used on the right person at the right time.

Why Aerobic And Strength Need To Come First

On the EST side, OPEX uses the MAP continuum to build aerobic progression across about a year. On the anaerobic side, they talk about a separate continuum for “pain.”

Those two continuums sit next to each other, not on top of each other. One does not automatically turn into the other, but a strong aerobic base is treated as a prerequisite before a client earns anaerobic work.

Two big boxes to check before a client touches anaerobic training:

• Aerobic base: They can already tolerate and repeat structured aerobic work.

• Strength and power: They are strong enough to actually express high power.

The light bulb analogy explains it well. If a bulb can get very bright, it has the capacity to create a lot of internal wattage. That is like a strong client with good mechanics. That person can now express meaningful anaerobic work.

If someone is weak, new to resistance training, and moves poorly, they are not producing enough power to hit the anaerobic system. They are not doing pain sessions. They are just sweaty and tired.

That is why OPEX ties resistance training quality to anaerobic training. You do not need to be strong to ride a bike easily for 30 minutes, but you absolutely need power and skill to sprint hard and recover from it.

Simple, Not Fancy: How OPEX Builds Anaerobic Progressions

In the Thursday labs, coaches broke into groups and built simple anaerobic progressions, all cyclical, over eight weeks.

A few key ideas came out of that work:

• Simple prescriptions are harder, not easier, when done right

• Complex mixed-mode pieces hide the real contraction rate

• The “sexiness” is in the execution, not the spreadsheet

A messy session might look like: 10 fast burpees, then a bike sprint, then jump rope, then repeat. It feels hard, but the turnover is inconsistent and the stimulus is blurred.

A clean anaerobic session is more like: 1 hard machine, 1 clear work time, 1 long rest time, repeat for a small number of sets.

Coaches often looked at their 8 week plans and said, “Is that it? It looks too basic.”

The answer was yes, it should look basic. The hard part is:

• Hitting the right power in each interval

• Resting long enough

• Making efforts repeatable, not sustainable

If the client does one minute hard, then rests, they need to come back and match that effort across sets. That is what trains the anaerobic system, not a complicated list of movements.

Why Anaerobic Training Is So Messy In Groups

Office hours brought up a big practical question:

What happens if you try to run an anaerobic progression in a group training gym?

The short answer from OPEX: it turns into a mess.

Picture 20 people doing a “pain” piece like thrusters and pull-ups:

• 5 newer members are doing ring rows and goblet squats, resting often. They are basically doing cluster-style strength work, not true anaerobic intervals.

• 12 or so middle-of-the-road members are grinding with empty bars and single pull-ups. Turnover is slow, fatigue builds, and the piece never hits real anaerobic power.

• 3 advanced members are going unbroken and actually getting the intended dose.

The same thing happens on a simple bike protocol if the group has a wide spread of fitness. Some folks will default to tough aerobic work because they simply cannot produce enough power for long enough to tap into anaerobic pathways.

With anaerobic training, dose response is everything. You are chasing:

• A clear lactate buildup

• Enough rest to recover

• The ability to use that lactate as fuel over time

If only a tiny fraction of the room is actually getting that dose, then from a programming standpoint, you are not doing what you say you are doing.

That is why OPEX tends to reserve anaerobic progressions for:

• Individual design

• Very advanced group subsets

• Sport specific training blocks

General population groups usually do much better with smart strength work and progressive aerobic training.

When Anaerobic Work Actually Makes Sense

During the lecture, three main “utility buckets” for OPEX Pain were laid out.

1. Sport specificity

This is the clearest and strongest reason to use anaerobic training. Examples include:

• Short to mid-distance track athletes doing true sprint intervals

• Field sport athletes like football players doing 10 to 20 second high power bouts with long rest

• Competitive CrossFit athletes who need serious lactate buffering to survive event formats

In these cases, the sport demands that the athlete handle those painful, unsustainable efforts.

2. Metabolic stress and body composition

Some coaches look at anaerobic work as a way to boost fat loss, since the sessions are very taxing. The problem is cost.

Anaerobic training is expensive in every way:

• It needs high motivation and intent

• It hits the nervous system hard

• It takes a lot of recovery

You can get a strong metabolic response with much lower cost tools, like tough but controlled aerobic intervals. So while you could use anaerobic work here, it is usually a poor choice.

3. Boosting aerobic capacity with a “lactate booster”

This one landed with a lot of coaches.

Think of a serious endurance runner, not a Sunday jogger. They race 10k and want to handle late-race surges and hills better.

At 6k, a hill appears:

• If they have trained some anaerobic “booster” work, they can handle the spike in lactate and keep going.

• They could choose to back off and avoid the hill effort.

• Or they could attack it and then bonk, because their system cannot clear and reuse the lactate.

In this case, small doses of anaerobic training support the aerobic system in the moments when the race temporarily jumps above steady pace.

Meet Assistant Instructor Steve Volke

Week 5 also highlighted one of the assistant instructors, Steve Volke, owner of OPEX Regina.

Steve and the lead instructor have been side by side since the early OPEX Gym days. He opened his gym the same year and has coached for a long time.

A few reasons he is on the instructor team:

• He is a strategist in how he runs his business and his coaching.

• He is thoughtful in how he builds relationships, programs, and systems.

• He has a powerlifting background and understands strength at a deep level.

• He consistently runs one of the most profitable OPEX gyms.

Steve also mentored OPEX Gym owners and CCP coaches for years and now supports the Method cohort in labs, office hours, and Slack, along with the other assistant instructors.

What Comes Next: Writing Complete Training Programs

Week 6 of the OPEX Method shifts from separate pieces to the full picture: writing training programs.

Coaches move from:

• Macro cycles, long term planning

• To mesocycles, shorter phases

• Down to daily program design

The goal is to combine resistance training, aerobic work, and, when appropriate, anaerobic work using clear principles of concurrent training.

The big theme stays the same though. Keep it simple and make it transferable to the client’s real life. Fancy exercise selection is not the point. Moving people forward with clear intent is.

The program also continues to highlight the difference between knowledge and wisdom. Knowledge is understanding ATP, rest ratios, and MAP models. Wisdom is taking that information and using it to help a client in a way that fits their goals, capacity, and lifestyle.

If you want to go deeper into this kind of thinking, you can learn more about the OPEX Method education and mentorship.

You can also watch strength coach and DPT Dr. David Skolnick document his experience going through Week 5 in his vlog on the OPEX YouTube channel.

Key Takeaways From Week 5: Pain With A Purpose

Anaerobic training looks cool on paper, but it is expensive and only useful for the right person, at the right time, with the right dose.

For most general population clients, a smart blend of strength and aerobic work will cover almost every goal they care about. For advanced and sport-driven clients, targeted anaerobic progressions can be a powerful tool, as long as the coach respects the cost.

If you coach, take some time to ask: who in your roster has actually earned this kind of work, and who needs you to stay focused on the basics.

If you want more structure, support, and a clear model to follow, consider joining a future OPEX Method cohort and turn knowledge into real coaching wisdom.

The livestream runs across YouTube, LinkedIn, and Facebook. Questions are welcome during the stream and after. If you have a question, add it in the comments where you watch.

The team reviews them and answers in the next live session. There are no silly questions. If something is blocking you, someone else is likely stuck on the same thing.

Curious about joining a future cohort or want the full curriculum?

Get the overview and next steps inside the OPEX Method mentorship and CCP Level 1.

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