Why many get stronger by working out with less intensity but every day, with no rest days?

Question

Physiotherapists usually make you do several light sets every day in order to strengthen your healing injuries.

Military training consists of lots of calisthenics, almost daily.

Not so long ago, it was not uncommon that Lorries had no power steering. Lorry drivers developed huge arms, merely by doing their job day after day with that vehicles.

The same for miners and heavy-duty workers in general around the 1900s.

I remember too, some very famous "body-building-at-home" courses from the 1950s that were very famous still in the 80s in the country where I live, that resembled the Charles Atlas method. That courses consisted of several exercised to be done daily, one only set per each exercise. Every 15 days, the exercises changed.

Well, that is my question. If reducing the volume to one only set per exercise obviously reduces the chances of over-training and injury, why not training a single set per exercise, every day? It seems to me a more progressive way of strength training. Less repetitive stress on your joints, less micro-trauma and less recovery time needed, but all that, more often.

We have evolved to be in a constant fight against the environment. I am sure our ancestors didn't climbed the trees nor ran to escape predators twice a week, with rest days in between.

Answer 1

Physiotherapists usually make you do several light sets every day in order to strengthen your healing injuries.

Yes.

If reducing the volume to one only set per exercise obviously reduces the chances of over-training and injury

It doesn't obviously reduce the chances of over-training and injury.

why not training a single set per exercise, every day?

Because your 1 rep maximum increases more quickly when you do a few high-load/low-rep sets every couple of days.

You need to take a rest day in this setting because the high-load causes a period of recovery where your performance is reduced and you will not be able to repeat that workload let alone increase it by a couple of pounds.

It [a single set per exercise, every day] seems to me a more progressive way of strength training.

This depends on your definition of progressive.

Less repetitive stress on your joints

If you do 3x5, 3 times a week, that's 45 work-weight reps per week. If you're doing one set of 5 every day, that's 35 work-weight reps per week.

If you include warm-up sets (for example: 5 reps empty bar, 5 reps empty bar, 5 reps heavier, 3 reps heavier, 2 reps heavier) that's 20 reps to warm-up to your work weight.

On a standard 3x5 program, that's 35 reps (20 warm-up, 15 work), 3 times per week, for a total 105 reps per week.

On a 5 reps per day program, that's 25 reps (20 warm-up, 5 work), 7 times per week, for a total of 175 reps per week.

less micro-trauma

True.

and less recovery time needed

Probably, but a full day less? A single work set is sufficient to stimulate about 80% of the adaptation of the full 3x5. Because of this, I don't expect that recovery time would be cut in half.

I am sure our ancestors didn't climbed the trees nor ran to escape predators twice a week, with rest days in between.

That is also true.

Answer 2

One set per exercise is nowhere near the volume you're talking about in those scenarios. If you're a coal miner and you're lifting moderately heavy things all day, you're going to build strength in those muscles. Doing a single set of everything is going to result in very little strength gains. Not to mention that, barring any kind of warm ups which don't appear included in your concept, doing a single moderately-intensive set sounds like a good way to injure yourself, too.

Answer 3

I must disagree with the above mentioned, my personal experience has been to the contrary.

I deadlift 5 or 6 days a week with no additional psychological stimulus (music, yelling, screaming etc), approach the bar and pull my 85% CALMLY for 5 singles. Also at 80% Daily is 1x5, Military Press, Barbell Row,Bench Press, and 1x8 curls/tricep depending on mood. My weekly volume is evenly spread, which I believe is giving me maximum protein synthesis uptime for a natural lifter.

I advice that you should keep your volume low, the act of training every day will overload your muscles by way of frequency. Your 1x5 lifts should begin to get 'easier, more punchy'. At that point you increase volume by way of additional reps ie. 1x8.

When 1x8 is tight and clean, increase intensity marginally to facilitate another round of 1x5. If at any time, you have acute soreness, tendon pain or malaise take a 1 week deload/break. You may rotate other accessories in the 1x8 if you wish.

Keep the volume and intensity managed avoiding "grinding" reps out. Rinse and Repeat.

References: Jason Blaha, "Let's Talk About Full Body Training EVERY Day & The Natty Lifter" https://www.youtube.com/watch?v=soJK_VLaTno&t=689s