What is Strength Endurance?
Strength Endurance is -quite simply- the ability of a strength pattern / movement to endure through multiple contractions.
So if a single maximal contraction, a one rep Max (1RM), is absolute strength; then a 10-rep or 100-rep Max could be classified as Strength Endurance.
As you can tell, what qualifies as Strength Endurance can be quite broad.
So maybe it will be more helpful to say what it’s not. Strength Endurance is book-ended by qualities where endurance (or) strength is no longer relevant to the equation: maximal strength and muscular endurance work.
Essentially, to be maximally strong or extremely enduring, you have to organize your physiology to that end of the spectrum.
A powerlifting has no need to be enduring, and the ultramarathoner must be able to create light, highly repeatable contractions to be successful.
The whole idea of being a “functional” athlete is that you don’t organize and optimize your physiology for a single task.
The middle ground is Strength Endurance.
To avoid being too generic, let’s say anything below a 5-Rep Max doesn’t require a meaningful amount of endurance, and any series of continuous contractions above 100 doesn’t have a meaningful strength input.
Two Notes: First…yes, strength supports endurance and vice versa, but that’s not what we are talking about today. Second…these zones are -frankly- made up, and shouldn’t be taken as gospel.
Types of Strength Endurance
Therefore, each of the following events could be described as requiring Strength Endurance…
-10 Rep Max Front Squat
-Max Unbroken Strict Handstand Push-Ups
-40 Ring Muscle-Ups for Time
-3 Rounds for Time: 12 Deadlift @60%, 12 Box Jumps
-1k Row Time Trial
If you didn’t catch it, I’ve layered the examples from least to most contractions…
-10 → 20 → 40 → 72 → 100
However, the number of contractions is just one way to think about strength endurance.
You also want to consider the joint angle velocities (movement speed), global vs. local fatigue, the type of contraction (eccentric, isometric, concentric) and the skill & coordination requirements.
An athlete will need a unique combination of each of these qualities to be successful in these example tasks.
Assessing a CrossFit Athlete’s Strength Endurance
Too often we examine an athlete’s abilities (or our own) using a singular lens.
Athlete A struggles with long events? Oh, it’s an issue with aerobic capacity.
Athlete B can’t squat clean enough weight to be competitive? Oh, it’s an issue with maximal strength.
It’s very possible that Athlete A is great on long events that are cyclical, like a sprint triathlon, but struggles in a mixed modality environment, like “Murph.”
And it’s very possible that Athlete B has a back squat max higher than his competitors, but lacks the strength in the specific ranges needed to be a proficient Weightlifter.
My point is, as a coach or self-coached athlete, you have to look at the big picture of an athlete’s struggles, and “try on” various lens as you do so.
Create a battery of tests specifically surrounding an athlete’s weaknesses that will test different qualities.
Let’s take the following Avatar.
23 y/o Male
His main goal is to perform highly in the Sport of Fitness / Competitive CrossFit. He has been training for fitness specifically for about 1.5 years.
He played Rugby through university and mainly did powerlifting and accessory-style weight training in the off-seasons.
A movement screen revealed several mobility limitations mainly revolving around the hips and shoulder girdle.
In testing his clean and jerk, he power cleaned and push pressed 295lbs. His “Grace” time was 2:17 (4.6s/rep).
He can regularly string sets of 5 muscle-ups when in isolation, but struggles for doubles in qualifier-style workouts.
He deadlifted 575lbs in testing, and completed 40 reps for time @ 315lbs in 3:13 (4.8s/rep).
If George were my athlete, this is likely the sort of information I would have about him early in the testing and training process.
Some of the initial testing simply allowed me to identify which characteristics pose as problems. Basically, my tests allow me to construct better tests.
For example, it’s obvious that George is super strong and it’s clear his technique and mobility aren’t where they need to be, so it would be easy to say that it’s just a matter of developing the mobility so he can get in better positions and that will allow him to hit big weights.
This might be true, but it’s not the whole picture.
If I was just an issue with mobility, something like the 40 Deadlifts for Time @ 315lbs should be his jam. Most athletes can hit 54% of their 1RM close to 40 reps unbroken.
Knowing athletes smaller and weaker than him will perform better than him on a barbell only strength endurance test tells us a significant amount about his ability to endure in the hinging pattern.
It could be that George’s hinging mechanics and mobility are so poor is can’t breathe effectively enough to exchange any air.
Or it could be that George generates so much muscular tension that he can’t get oxygen-rich blood into the muscle and his performance drops dramatically after the first set.
As you can see, things get complicated, but often they have simple solutions.
Start by watching the video of George performing the test.
Can you hear and see him breathing in the correct sequencing for a deadlift that is appropriate for ~55% of his 1RM?
Does it look like each rep is a maximal effort with a high level of neural drive?
Are his hinging mechanics sound and his movement smooth?
So what does this have to do with Strength Endurance?
Everything. Strength endurance is about developing both a physical quality AND a skill. This includes the ability to be able to breathe and move effectively for the given task.
Often athletes with a strength background don’t know how to tune back rigidity (tension gradient) to make their patterns more enduring.
Often athletes with an endurance background don’t have the ability to brace their spine effectively while breathing to move moderately heavy load quickly.
Programming for improvements in Strength Endurance isn’t just about giving progressive doses of high-rep barbell or gymnastics work. It need to be a part of a comprehensive program addressing the athlete’s movement flaws, and building their economy of movement.
Programming to Improve Strength Endurance
Avatar #1: George
Limitation: Hinging Strength Endurance
Examples: “Randy”, FT: 40 DL @ 315lbs, Open 20.1
A1. Hip Flow (3 x 4 / way) rest 15s
A2. Air Squat Hold with Rig Support (3 x 20s) rest 15s
A3. Banded Good Morning (3 x 5) @ 40×0 | rest 15s
B. Supine Hamstring Stretch – 2x per leg (10s Passive Stretch + 10s Isometric Closing Joint @ End Range + 10s Isometric Opening Joint @ End Range)
C. Deadlift Positional Breathing, 3 Rounds @ 95lbs
-3 Belly Breaths with Barbell on Floor (but keep tension on bar)
-3 Deadlifts; 1:1 Breath-to-Rep Ratio, holding breath below the knee
-3 Belly Breathing in Lockout of Deadlift (relaxed upper back, tense glutes)
D. Deadlift (2 x 126.96.36.199) @ 60% @ 30×1, 1:1 Breath Ratio
For Time // 12-8-4
-No-Contact Power Snatch 95lbs
(Rest 1:1 & Repeat)
-500m Row @ 5k TT Pace +8-10s
-12 Sumo Stance Good Mornings 65lbs @ controlled tempo
-25 Seated Banded Hamstring Curls – light tension, fast reps
Session Intent: George has more than enough strength in his hinging pattern, the issue is mobility and fatigue resistance (endurance). He carries too much tension and can’t breathe as a result. Therefore, we start the session with low-tension movement work and positional breathing. Then comes the strength endurance work, but still he is forced to hold certain conditionings (tempo, breath ratio). This is then applied in a mixed modality setting, but is following by more endurance work to reduce any residual tension built up by the Sport element, while building further fatigue resistance to the hinging pattern.
Avatar #2: Sammy
Limitation: Upper Body Pressing Strength Endurance
Examples: Open Workouts 12.4, 17.4, 19.3, 19.4, 20.1
A1. Ski Calories (3 x 10) damper on 1, light tension | rest 15s
A2. Seal Push-Ups (3 x 8) rest 15s
A3. Air Runner Calories (3 x 8) @ smooth pace, form-focused | rest 30s
A4. Wall Walk (3 x 2) rest 15s
B1. 1 Power Clean + 5 Push Jerk (4 Sets) Rest 20s
*start @ 60% of Jerk & climb to heavy
*push jerks must be Touch-N-Go (no re-dip in front rack)
B2. Heavy Double Unders (4 x 30) Rest 2:00
-3 Ring Muscle-Ups
-6 Strict Handstand Push-Ups
-12 Calorie Ski @ 2k Time Trial Pace -2-3s
*Rest until 7 out of 10 recovery
For Quality | Accumulate the following however you please…
-2:00 Wall-Facing Handstand Hold
-2:00 FLR Hold on the Low Rings
Session Intent: The session starts with relatively low complexity quasi-pressing movements, mainly to prep the aerobic system and get blood movement in and out of the tissues that will be taxed in the session. Then into some pressing-focused strength work in a sporting context. The interval work is has self-regulated rest, as an athlete’s pace on intervals with high movement interference can degrade quickly, causing them to fail fixed intervals. The session is ended with some accumulation of muscular endurance and midline work to help support the more strength-related adaptations.
Like other physical traits an athlete needs to develop, improving Strength Endurance is simple for the novice.
Do you need to get stronger? Do more strength work.
Do you need to be more enduring? Do more moderate effort, prolonged cyclical work.
Do you need better strength endurance? Do things that demand repeated bouts of strength.
Remember, coaching is more of a practical and logistical game than creating the perfect training program.