Correct, most people will not be as efficient at singles if they have not been practicing them. In addition the correlation between 5RM and 1RM is not exact. So, if your 5RM decreases by X amount your 1RM won't necessarily decrease by X amount.
I understand that 1RM are not a part of the SS programme. However, let's not lie: everyone has a go at their 1RM and taking it further at some point.
What i wish to query is what appears to me to be an odd variety in the difference in weight between a 5RM and a 1RM in the same lift.
Scenario. A couple of years ago when i was training the squat (without any significant programming & prior to having discovered the SS method) i had - more through fluke than anything else really - gotten my squat up to 112.5kg for 5RM and 134.5kg for a 1RM. Now, recently curiousity got the better of me, and i opted to give the 1RM a go. Now, at this point my 5RM is a paltry 105kg, but i couldn't get more than 115kg for a 1RM. So why was there a difference of 22kg the first time i did this, but only 10kg this time? My method for doing this was essentially the same as that which i used two years ago - going up in weight gradually, keeping the reps low to conserve energy/strength for the 1RM attempt.
The only thing i can think of is that since my commencing SS, i have never - other than the aforementioned recent 1RM attempt - done sets of less than 5 reps (excluding warm-ups), whereas when i was 'training' 2 years ago, while i wasn't performing the squat more frequently than 2 days per week, i was lifting sets of low reps regularly.
I have noticed exactly the same thing with my bench press.
Have I answered my own question, or is there more to this?
Correct, most people will not be as efficient at singles if they have not been practicing them. In addition the correlation between 5RM and 1RM is not exact. So, if your 5RM decreases by X amount your 1RM won't necessarily decrease by X amount.
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It is conducive to think of it through the lens of the two-factor model of sports performance. A one RM for a novice will not act as a training event in the same sense that three sets of five does; rather, a one RM is more of a sports performance. Therefore, it has to be practiced as such, but with a 115 kg one RM it is more productive to get strong by DTFP and to worry about your one RM later. At that point you should do some singles if your aim is to be proficient at doing singles.
My point - by implication - is that 5 rep strength is surely just that: 5-rep strength. Lets' look at the following scenario. I have a 5RM of 110kg. Joe has a 5RM in the same lift of 115kg. On occassion (say once per week) I throw in some doubles and single-rep sets, whereas Joe religiously sticks to 5 rep work sets. Because of this, while my 1RM is 135kgs, Joe's is only 125kg - even though he lifts more than me for 5 reps. Who's is 'stronger'?
The test of "who is stronger" is generally done with a 1RM and some adjustment is made for body weight (or with weight classes). Obviously, it's not a perfect system as someone could have a bad day at their meet and miss a lift, but still be capable of hitting that weight if something wasn't off. There is no perfect way to measure strength, indeed in Strongman they do it very differently. So, just decide how you want to measure it and realize that your skill/familiarity with that way of doing it will have bearing on your expression of your strength.
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In the scenario that you provide, you are stronger than Joe because strength is the production of force against an external resistance; 135 kg produces more force in order to lift the weight than 125 kg. For that reason, you are stronger than Joe. However, Joe will get stronger than you if Joe is of equal athletic ability, recovers adequately (drinks milk like a baby calf and sleeps like one too), and religiously does his Fives. Three sets of Five gets your Average Joe strong, and it gets him strong faster than anything else, including singles and doubles.
I never thought of strength being a relative attribute. Obviously, there is a degree of relativity between 2 or more persons with regard to bodyweight, but ultimately we all deal with the same force of gravity. That being said, perhaps there's an element of endurance tied to strength as a physical attribute and that this 'strength-endurance' comes into play more the greater amount of reps are demanded.
For strength, 1RM is the measures the ability to produce the most force, 5 reps does not predict who has the highest 1RM. You can have a contest with Joe with whatever terms you want, but 135kg is more than 125kg and you win on strength even if your bodyweight is 150kg and his is 45kg.
A more interesting question than "who is stronger?" in a 5 reps internet speculation contest is "who would you rather be?" -- a guy who can make a 1RM 23% above his 5s or one who gets less than 10?
That's what i thought.
Since (as highlighted by yourself and monsieur Courtland above) to improve 1RM strength, one must practice 1RM lifts, and that 1RM best indicates the ability to move the most force (s-t-r-e-n-g-t-h), then it must follow that to get stronger, in the surest definition of the term, we ought to be practising those max singles from time to time?
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