When I first started training, I wanted to be the type of person who benched and squatted more than everyone else in the gym. In that pursuit, my body was willing to let my ego take it to some pretty scary places.

I'm older now and, truth be told, those things are still important to me. I still want to be the type of person who lifts heavy weights (and who looks like he does), but my training goals are more about building usable strength and sustainable fitness rather than proving my worth one lift at a time.

I also want to be able to climb a fence, sprint down the street after my kids, or go on a multi-day hike in the mountains without needing to convalesce for two weeks afterward.

In the quest to be the biggest, strongest person in the room, sometimes we concentrate our efforts in one area so much that we become one-dimensional – a one-trick pony that moves like a cinder block and thinks taking the stairs is "cardio."

If you want to have it all – strength, capacity, and recoverability – you need a plan that balances a variety of stressors. That's where work capacity comes in.

Work capacity is the total amount of work you're able to perform and recover from, across a range of different intensities, time domains, movement patterns, and energetic pathways. You could say it's a measure of a person's fitness. I'd say usefulness, too.

Building work capacity is like diversifying an investment portfolio – you can concentrate most of your assets in one area while building in enough variety to insulate you from downturns in the market.

Done right, strategically-implemented work capacity blocks can be powerful training tools. Not only are they an effective way for training multiple qualities at once, they also dissipate fatigue and inflammation, allowing you to go even more "all-in" on subsequent high-intensity training.

Manage the Supply Chain

Building great work capacity is all about managing the way energy is produced, delivered, and ultimately utilized by your body. If there's a delay or inefficiency at either end of the chain, the whole process is thrown off balance.

Cardiac output is on the front end of the chain. It's part of the central work capacity that determines how efficiently your cardio-respiratory and circulatory systems deliver oxygen and nutrients to front-line muscles for use.

Energy utilization is part of peripheral work capacity and it's on the back end. It's an entirely local phenomenon that depends on capillary density and mitochondrial volume. The more contact points your muscle has with the blood stream to exchange oxygen and discharge carbon dioxide, and the greater the number of mitochondria in the cells waiting to convert oxygen molecules into ATP, the smoother the process goes.

Because the chain is only as strong as its individual links, and because, in this case, the links require entirely different things to function optimally, the training stimulus has to be different to stoke the type of adaptations we want at each step.

Here's how we do it.

Work Capacity

Central Work Capacity

Building central work capacity involves accumulating a high volume of work in a way that maximally stresses the system as a whole, but doesn't overload any specific local tissues with too much volume.

Here are three methods to accomplish this:

1 – The 30/30 Circuit

I first came across this in Pat Davidson's MASS programs and it changed the way I program work capacity forever. Here's the set-up:

Ten compound exercises – think squat, deadlift, bench press, lat pulldown, overhead press, etc. – all performed for 3 rounds of 15 reps. The reps for each exercise have to be completed in 30 seconds or less. Alternate between upper and lower body exercises.

Rest for 30 seconds, then move to the next exercise.

Between rounds, catch whatever is left of your breath for 90 seconds. The whole workout should take 33 minutes.

The beauty of this workout is that it allows you to accumulate a ton of systemic volume from round to round without ever exposing any one pattern or muscle group to a high level of mechanical tension. The 15-rep prescription, coupled with 30-second rest periods, provides just the right combination of time pressure and gamesmanship to keep the workout interesting and motivating.

2 – Mixed Modal HIIT

This is the domain of repeat sprints or intervals, but spread out across multiple machines. The goal is to shuttle blood to different areas of the body – like squeezing toothpaste back and forth from one end of the tube to the other – using a variety of intermediary exercises.

Pick 2-3 exercises like the bike, treadmill, rowing machine, sled, or battling ropes. Begin by sprinting through the first exercise for 15-30 seconds, then rest or actively recover for 60-90 seconds. Do 3-5 sets on that exercise before moving to another drill, machine, or piece of equipment, where you repeat the drill.

It works out to be about 5-7 minutes per exercise for a total workout time of 10-20 minutes (depending on whether you do 2 or 3 exercises). Expect to be out of breath... a lot.

3 – High-Leverage Density Circuits

Density training is a straightforward method for accumulating huge amounts of volume as measured in tonnage and affected tissue. The high-leverage part refers to the type of exercises used: big, multi-joint movements that lend themselves to heavier loading. No biceps curls or front raises here.

Choose five compound lifts. Squat, bench press, deadlift, lat pulldown or pull-up, and leg press all work well, but feel free to make substitutions. Choose weights equal to 20RM for each.

Start a 20-minute timer. Perform each exercise for 10 reps, stopping only as long as you need to catch your breath before moving to the next one. Count the number of rounds completed and tonnage moved. Next workout, do more.

Dips Exercise

Peripheral Work Capacity

Cardio-respiratory fatigue is the limiting factor in central, or systemic, work capacity training. Here we're seeking optimizations at the other end of the chain – in the muscles themselves – through a combination of metabolic stress, nutrient depletion, hypoxia, and cellular swelling.

Don't be put off by the technical terms, though. These are just the mechanisms by which local changes in tissue quality are thought to work. The practical application is actually straightforward in that you use long duration sets or break it up into waves.

1 – Long Duration Sets

Think of this as the equivalent of doing steady-state training, like cardio, but just for one muscle or muscle group at a time.

You'd pick an exercise, say, military press for shoulders, using a weight equivalent to your 15-20RM. Perform that exercise for 3-4 sets, hitting failure on each set and adding weight if you can go beyond the 20-rep threshold.

Rest 3-5 minutes between sets. Then move onto the next body part. This is usually done in an upper body/lower body training week split, so you'd pick 2-3 exercises for upper body and 2-3 exercises for lower body. Either way, each workout is between 4-6 exercises overall.

The idea here is to crank the oxidative stress, acidity, and fatigue up to ten, causing a massive disruption from homeostasis, then back off with enough rest to fully replenish the system before going again.

These exercises work best:

Upper Body Push

  • Bench Press
  • Incline Press
  • Dumbbell Press
  • Overhead Press
  • Dip

Upper Body Pull

  • Weighted Chin-Up
  • Lat Pulldown
  • Cable Row
  • Chest Supported Row

Lower Body Push:

  • Barbell Squat
  • Split Squat
  • Hack Squat
  • Leg Press

Lower Body Pull:

  • Barbell or Trap Bar Deadlift
  • Dumbbell Romanian Deadlift
  • Leg Extension
  • Leg Curl

2 – Incomplete Rest Training

Bodybuilding guru Vince Gironda was an early champion of incomplete rest sets. His favorite technique, known as the "honest workout," was an 8 x 8 workout using 15-30-second rest intervals between sets.

Using Gironda's 8 x 8 template, pick 3 exercises per muscle group and do 8 sets of 8 reps (24 total sets). Use weights equivalent to your 15RM for each exercise. Rest 20 seconds between sets.

Using chest as an example, the workout would look like this:

  Exercise Sets Reps Rest
A Flat Barbell Bench Press 8 8 2-3 min.
B Incline Dumbbell Chest Press 8 8 2-3 min.
C Cable Chest Flye 8 8  

For hamstrings:

  Exercise Sets Reps Rest
A Barbell Romanian Deadlift (RDL) 8 8 2-3 min.
B Glute Hamstring Developer (GHD) or 45-degree hyperextension 8 8 2-3 min.
C Leg Curl 8 8  

The idea is to think of this as interval training for each muscle group. You deliberately take your foot off the gas before your tank is dry, allowing just enough time between rounds to restock your supplies.

Each successive wave, although sub-maximal in weight, builds on the one before it, culminating in a tidal wave of volume that feels hard in the moment, but allows for quick recovery between sessions since you never really hit a point where energy production within the cell is taken to its furthest extreme.

An Appeal to Logic

Heavy weights will always provide the quickest, most direct path to growing bigger, stronger tissues. However, I've never met a person who's been able to sustain linear size and strength gains year after year without breaking down or burning out.

Programming dedicated training blocks distinct from high-intensity work allows you to fill in the holes in your conditioning while maintaining volume and giving your system a chance to recover between mechanical tension blocks.

Related: A Supplement That Boosts Work Capacity

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