Hypertrophy: An increase in the size of muscle tissue (aka “muscle building”).

Read time: ~5 mins

Any company selling home workout equipment is busier than ever with the current pandemic, a significant surge in demand. Now, we can’t all have access to 100s of kgs at home, so what can we do with our dumbbells in the shed? Or our kettlebell that may have spent some of it’s time acting as a door stop (Stop judging me).

How low load compares to heavy load resistance training?

Schoenfeld et al, 2017 performed a meta-analysis on 21 studies showing that low-load training can produce similar hypertrophy responses to that of heavy load training when effort is high, nearing failure, all studies included in the analysis used momentary muscular failure as the point of set termination.

Hypertrophy can be achieved across a wide range of loading zones and therefore spectrum of rep ranges.

Finding your rep range with low load.

“Momentary muscular failure”, is needed with light loads to optimise hypertrophy. I’ll save the lesson on muscle & nerve physiology for another day. Simplified, muscles are activated according to demand for force (or load in this case). The big “guns (pun!)” (aka high-threshold motor units) are recruited with high loads but aren’t recruited with lower loads until the set becomes fatiguing, in an effort to maintain force output. Research shows when training with low loads we should aim to be near failure (Schoenfeld et al, 2019).  

Failure could be a very different number of reps for “John” as what it could be for “Mary”, even if they have the same estimated 1 rep max (maximal strength). Muscular failure is the inability of activated muscles to complete another repetition without assistance. Going to failure would be therefore easy to identify, however near failure is a different story.

So, how do we judge near failure when multiple reps can be performed? Resistance training–specific rating of perceived exertion scale and reps in reserve proposed by Zourdos et al 2019.

RPE:RIR scale adapted from Zourdos et al 2019.

Can you go too light to build muscle?

In strength training, a load lifted is often quantified as a percentage of a 1 rep max (%1RM) or a repetition max (i.e 8 rep to failure = 8RM). Lasevicius et al 2018, showed there is such thing as “too light”, performing similar number of sets to failure at 20% 1RM produced less hypertrophy than sets in the 40-80%RM groups.

Once you can do the standard variation either take your sets to near failure with increased reps when working out or further modify to increase load and therefore strength demands. All will assist in hypertrophy.

In article 3, we’ll discuss how to structure a home workout with a combination of bodyweight movements and low loads to optimise your goal of building muscle with limited resources.


  • Lasevicius, Thiago & Ugrinowitsch, Carlos & Schoenfeld, Brad & Roschel, Hamilton & Tavares, Lucas & De Souza, Eduardo & Laurentino, Gilberto & Tricoli, Valmor. (2018). Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy. European Journal of Sport Science. 18.
  • Schoenfeld, Brad & Grgic, Jozo & Ogborn, Daniel & Krieger, James. (2017). Strength and hypertrophy adaptations between low- versus high-load resistance training: A systematic review and meta-analysis. Journal of strength and conditioning research. 31.
  • Schoenfeld, Brad & Grgic, Jozo. (2019). Does Training to Failure Maximize Muscle Hypertrophy?. Strength and conditioning journal
  • Zourdos, Michael & Goldsmith, Jacob & Helms, Eric & Trepeck, Cameron & Halle, Jessica & Mendez, Kristin & Cooke, Daniel & Haischer, Michael & Sousa, Colby & Klemp, Alex & Byrnes, Ryan. (2019). Proximity to Failure and Total Repetitions Performed in a Set Influences Accuracy of Intraset Repetitions in Reserve-Based Rating of Perceived Exertion. Journal of Strength and Conditioning Research.