Finding your Strength Head: Introducing relative intensity

Finding your Strength Head: Introducing relative intensity


The CrossFit London programme has many objectives, one of which  is to  help you find your strength head – shorthand for developing your strength knowledge. In this article we visit the basic language of weightlifting and how it relates to the concept of relative intensity.

When it comes to using weight; in simple terms, people think this: lift the heaviest weight you can, that’s your 1 rep max; then based on that you can lift 90% of it 3 times (3reps), 85% of it 5 times, 75% 10 times. If you do 3 rounds of 3 reps, that’s 3 sets.

So weight lifting is a mix of percentages, sets and reps, all based on a one rep max. Simples!

This is a great place to start, but to develop your strength head,  you need to develop your knowledge and insights into the strength game.

Some time ago, Zatsiorsky pointed out there are two types of  one rep maxes you can have: a competition 1 rep max, and a training 1 rep max.

A) A competition max is  where you get hyped up and get a PB  and scream a lot.

B) A training 1 rep max


However, often people skip the full definition of a 1 rep training max.

A maximum training weight  is the heaviest  weight you can lift  without substantial  emotional stress.

Damn. No screaming.

For athletes, the difference between the two is great. The example Zatsiorsky cites is that for athletes who lift  200 kg during a competition, a 180kg is typically above their maximum training weight. As a possible indicator, if your heart rate increases before your lift, that’s a sign of emotional engagement. Weightlifting is meant to stress your body, not your mind.

That’s the job of your partner and employer.

In short, if you screamed it up – it’s too heavy to use as a basis for regular training.

So, if you are calculating reps and sets using a 1 rep max, please, please use the right one; otherwise you’ll break. Maybe not today, maybe not tomorrow, but soon… If you want to properly test your 1 rep max, book a PT session with one of the training team.

If you have been lifting regularly for a while, you have probably begun to review strength literature and you are probably aware that lifting 80% of your 1 rep max provokes strength gain.

So, when lifting sets of 5, you’d probably like to put 80% of your 1 rep max on the bar. Everyone does that, but think about what it is you’d are actually be doing.

Let’s forget weightlifting for a moment, and talk about bricks. Imagine you are a labourer on a building site. Lets say we run a test to see how many bricks you can move in a day. For argument’s sake, let’s  say you can move 1000.

Normally in training we wouldn’t want to move the 1000, we would do 800 ( 80%) but many people want to set 5 reps of that. So there you are, lifting 5 x 800 =4000.

If you tried to do that in a day, you’d probably die.

Back to the weight room. So you can lift 100kg calmly as your 1 rep max. You’ve been told if you lift 80% and over of this figure, you are strength training. So, to keep the maths easy, if you lift 80kg, you are strength training. But do you lift that 80% five times?

As you see from my poor labourer example, the first 800 was probably easy, but the next 800, isn’t easy, the 3rd 800 is getting you to breaking point.

In short, 80% lifted multiple times, isn’t perceived by the body as 80%. It sees it as much, much heavier because of the volume. The bricklayer, is of course a silly example – but try and get the message rather than be sidetracked in the endurance aspect of the example.

In simple terms, because you are lifting in sets of multiple reps, a load of 67% of your 1 rep max lifted 5 times has a relative intensity of 79%. It feels like 79%, your body thinks it’s 79%. It is 79%

Putting 76% of you 1 rep max on your bar for 5, has the effect of being 88%.

70% feels like  =82%,

73% feels like  =  85%.

80% on the bar for 5, is like lifting 91%.

Relative intensity is the simple observation that volume, load and rest effects how your body feels and adapts to weight.

Coach Robb Rogers gives a fuller description here:

Remember your muscles are dumb, they don’t know or care about percentages. They just know what feels heavy.

According to Mike Tuchscherer; “The body responds to things like the force of the muscle’s contraction, how long the contraction lasts, and how many contractions there were. A percentage isn’t necessarily a precise way to describe this, as different lifters will perform differently.”

In take-home terms, if today you went to CrossFit London or CrossFit SE11, and during the strength session, you only got to 68% of your (proper) 1 rep Training max for 5; you actually hit the 80% in relative intensity. That’s the 80% you need to nudge your strength along.

For now, in our general programme, we are not obsessing about percentages; but those who do know their lifts, I hope will be grateful for this insight. For the rest of you, simply work to a set of 5 that you can comfortably lift, bearing in mind these RPE (rates of perceived exertion) as guidance.

On a scale from 1 to 10:

9: Heavy Effort. Could have done one more rep.
8: Could have done two or three more reps, but glad you didn’t have to.
7: Bar speed is “snappy” if maximal force is applied
6: Bar speed is “snappy” with moderate effort

After a while, I suspect a “five” you can do in class will be at an RPE between 7 and 8.

Once you bedded this concept of relative intensity into your head, you can look forward to many years of safe, effective lifting.

More “Strength Head” insights coming soon.

Grateful thanks to Coach Chet Morjaria @  Strength Education and to Coach Anthony Waller @ CrossFit London for the numerous corrections  and observations they supplied

Blackwork by Coach Kate Pankhurst, Certificate course piece @ Royal School of Needlework


Andrew - Author

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