One of the things that has fascinated me over the years as a personal trainer is just how difficult it can be to predict someone's strength simply by looking at them.
A bigger person isn't necessarily stronger. Equally, somebody with a relatively slight frame can sometimes surprise you with what they're capable of lifting.
I've seen this many times with clients. Someone can begin strength training using what seem like fairly modest weights, yet over the following months become capable of lifting loads approaching, and sometimes exceeding, their own bodyweight.
They haven't necessarily become dramatically bigger.
They've become stronger for their size.
And that's where the idea of relative strength becomes interesting.
Absolute strength versus relative strength
Most of us naturally think about strength in absolute terms.
If one person can squat 80 kg and another can squat 60 kg, the first person has lifted more weight. In absolute terms, they're stronger.
But imagine the person lifting 60 kg weighs 60 kg themselves, while the person lifting 80 kg weighs 100 kg.
The picture changes slightly.
The 60 kg person has lifted the equivalent of their entire bodyweight. The 100 kg person has lifted 80% of theirs.
That doesn't somehow make the 80 kg lift less impressive, nor does it automatically make the lighter person the better athlete. It simply gives us another useful way of looking at strength.
This is relative strength: considering the amount somebody can lift in relation to their own bodyweight.
Why I find this so interesting
I've worked with clients of many different shapes, sizes and training backgrounds, and I've learnt not to make too many assumptions about someone's capabilities from their appearance.
I've also seen how dramatically that relationship can change with training.
One client I worked with began with a fairly light bodyweight and relatively little strength-training experience. In his first session, a 22.5 kg barbell bench press for ten repetitions represented essentially maximal effort.
Around a year later, he could perform repeated sets of eight with 38 kg. His bodyweight had increased only modestly.
By this point, his lower-body training had progressed even further. He was performing sets of squats and Romanian deadlifts with weights greater than his own bodyweight.
I'm deliberately not presenting that as a scientific case study. It's simply one example from my own coaching experience of something I've seen repeatedly: bodyweight and strength don't necessarily increase together at anything like the same rate.
Someone can remain a relatively light person while becoming considerably stronger.
So should everyone be able to lift their bodyweight?
No.
This is where I think some of the information available online about strength becomes unnecessarily intimidating.
Search for strength standards and you'll quickly encounter tables telling you what a beginner, intermediate or advanced person “should” bench, squat or deadlift.
They can be interesting, particularly for people involved in strength sports, but I don't think they should become a pass-or-fail test for the general population.
A 25-year-old man who has trained consistently for five years shouldn't necessarily be judged against the same expectations as a 52-year-old woman beginning resistance training for the first time.
Training history matters. Age matters. Sex matters. Body composition, technique, limb proportions, previous injuries and the particular exercise being performed can all influence the number on the bar.
Even the exercise itself changes the meaning of “lifting your bodyweight”. A bodyweight deadlift is a very different proposition from a bodyweight overhead press.
There is no single bodyweight ratio that suddenly makes somebody “fit”.
Bodyweight can also be misleading
There's another reason I like relative strength as a concept.
Two people can weigh exactly the same amount and have very different physical characteristics.
Likewise, simply gaining bodyweight doesn't guarantee that somebody becomes proportionately stronger.
This is why I don't particularly like using bodyweight alone as a measure of somebody's progress.
The scales might barely move while that person becomes substantially more capable.
They may squat more, carry more, move better, perform more repetitions, recover more effectively and handle everyday physical tasks with greater ease.
If we only looked at the scales, we'd miss most of that progress.
Strength doesn't have to mean becoming a powerlifter
For most of the people I train, the objective isn't to achieve an enormous one-repetition maximum.
It's to become stronger while maintaining good movement, confidence and control.
That might mean progressing from bodyweight squats to holding a dumbbell. Later it might mean using a barbell. Eventually that bar might carry a substantial proportion of the person's bodyweight.
The individual steps don't necessarily look spectacular.
But add those steps together over six months, twelve months or several years and the difference can be enormous.
Progressive resistance training is very well established as a way of improving muscular strength, and those benefits don't suddenly disappear once we reach middle or later life. Research in older adults consistently finds meaningful improvements in strength from resistance training, including in people well beyond the age range of most of my clients.
That's one reason I think strength is such a useful thing to keep developing as we get older.
Perhaps the better question isn't “How much can you lift?”
It might be:
What is your body capable of now that it wasn't capable of six months ago?
That's the comparison I find far more useful.
If you weigh 70 kg, you don't need to be able to squat 70 kg tomorrow.
Perhaps you're currently comfortable with 30 kg.
If, through sensible and consistent training, that becomes 35 kg, then 40 kg, then 50 kg, something important is happening even if your bodyweight remains almost exactly the same.
You're becoming stronger relative to the body you carry around every day.
And if eventually you do reach the point where you can confidently perform an exercise with the equivalent of your own bodyweight, I think that's an interesting milestone worth recognising.
Not because a particular ratio magically makes you fit.
But because of what it represents.
Your body has become considerably more capable than the one you started with.