New "RIR 1-2 vs RIR 0" Study - Similar gains

[livingme7]

Study: https://www.tandfonline.com/doi/full/10.1080/02640414.2024.2321021

Summary:

Increases in quadriceps thickness (average of RF [Rectus femoris] and VL [vastus lateralis]) from pre- to post-intervention were similar for FAIL [0.181 cm (HDI: 0.119 to 0.243)] and RIR [0.182 cm (HDI: 0.115 to 0.247)]. Between-protocol differences in RF thickness slightly favoured RIR [−0.036 cm (HDI: −0.113 to 0.047)], but VL thickness slightly favoured FAIL [0.033 cm (HDI: −0.046 to 0.116)].

Lifting velocity and repetition loss were consistently greater for FAIL versus RIR, with the magnitude of difference influenced by the exercise and the stage of the RT intervention.

Key Points:

Terminating RT sets with a close proximity-to-failure (e.g., 1- to 2-RIR) can be sufficient to promote similar hypertrophy of the quadriceps as reaching momentary muscular failure in resistance-trained individuals over eight weeks, but the overall influence of proximity-to-failure on muscle-specific hypertrophy may also depend on other factors (e.g., exercise selection, order, and subsequent musculature targeted).

Due to high repetition loss (from the first to final set) when sets are terminated at momentary muscular failure, performing RT with 1- to 2-RIR allows for similar volume load and repetition volume accumulation as reaching momentary muscular failure across eight weeks, possibly influencing the overall RT stimulus achieved.

Performing RT to momentary muscular failure consistently induces higher levels of acute neuromuscular fatigue versus RT performed with 1- to 2-RIR; however, improved fatigue resistance overtime may attenuate acute neuromuscular fatigue and subsequent repetition loss (but may depend on the exercise performed).

Pros: This study design is very solid at trying to reduce confounding factors as much as possible.

Within person design: 1 leg trained to failure the other leg to 1-2 RIR

The participants did as many sets as their usual program

They used trained lifters.

Someone oversaw the training to ensure they don't slack off with the intensity

Findings: Overall similar gains

Regional Hypertrophy: the vastus lateralis slightly favored failure training

The rectus femoris favored non failure training

The Leg press was trained first with the leg extension afterwards, so this could indicate some important considerations regarding failure training and exercise order since we know that the rec fem grows better in the leg extension.

Fatigue: Higher in the RIR 0 groups but sadly only measured on training days, 24 and 48h post would have been interesting.

 

[unshakeablefaith]

@livingme7 Feel like we pretty much knew this already, most people are training in the 0-3RIR range or just to failure every set for the people who can’t count.

 

[dawn16]

@unshakeablefaith I think only the experienced ones are training 0-3 RIR. I think a lot of people’s 2-3 RIR is probably more like 4+ if we’re being honest, especially with legs.

 

[frustratedhusband]

@dawn16 Yeah especially leg extensions are fucken brutal. Crazy burn as early as 5-6 rir

 

[miles44]

@frustratedhusband i live for that burn. look forward to it every week.

 

[lovely_krystal86]

@frustratedhusband Leg extensions are one of those ones where you can keep going with an ever decreasing ROM until you hit “true” muscular failure. I like to go until I can’t fully extend all the way, and then try and get 3 more half reps super strict.

 

[frustratedhusband]

@lovely_krystal86 Yeah it's one of those perfect lengthened partials movements.

 

[palesa]

@lovely_krystal86 What do you think about stairs?

 

[dawn16]

@frustratedhusband So true. I always give myself some breathers on leg extensions to wash out that burn.

 

[palesa]

@frustratedhusband The hack squat for me, did them yesterday and burnt on the third rep, I still had five in the tank.

If it wasn't for having gotten used to the burn at some level I would've quit on four or five there instead of eight.

 

[rexiesf7]

@dawn16 What actually woke me up to this was, funny enough, a Mitchell Hooper video. He said that an amateur athlete assumes that when a muscle begins to slow down, they're at 8RPE. He says that an elite athlete goes to two reps from actual muscular failure, not mental failure.

A bit of a tangent, but I don't think RPE/RIR have to be a science. "Oh no, I was aiming for 2 RIR, but I think I did 1 RIR." Who cares? Just push every set close to failure.

 

[dawn16]

@rexiesf7 Yeah, learning to really push yourself to failure is a skill that takes lots of practice and focus. I’ll always lean towards pushing closer to failure knowing I’ll likely fall short.

 

[rexiesf7]

@dawn16 Yep, I've gotten fairly confident in my ability to do so by just using programs that revolve around a set pushed to failure.

 

[onepassionate1]

@rexiesf7 What programs have you been using?

 

[rexiesf7]

@onepassionate1 Team SKIP Training Protocol is one I did previously.

 

[harpazo777]

@livingme7 My RIRs are in the 1s and 0s on most things except like quad stuff, deadlifts etc.
RIR the fuck out of some bicep curls, sure. But on a leg press my head will pop before my legs quit. On those things I go higher volume and often 3/4 reps to keep it TUT instead.

 

[livingme7]

@harpazo777 I found single leg press or single legged belt squat is the only way to really get to true failure with legs

 

[harpazo777]

@livingme7 I do single leg leg press on my second leg day, I like them.
Belt squat would be nice to try!

 

[chole1]

@harpazo777

Belt squat would be nice to try!

Do you mean the one in which you tie the belt to the machine?

 

[harpazo777]

@chole1 Yeah, well it’s a belt squat machine.