In general, staying dedicated to your resistance training has been proven to build muscle mass and strength, along with plenty of other benefits. Even training just two or three times a week can make a difference to your muscle power over time. Recently, researchers explored how training your muscles in the more stretched or elongated position, like the deeper part of that squat, impacts muscle growth. Let’s take a look at the research.
The research
In a systematic review published in the journal Sports Medicine and Health Science, researchers wanted to know how performing resistance training at longer muscle lengths impacts longitudinal muscle growth compared to training at shorter muscle lengths. Put simply, does this specific way of training help your muscles grow longer rather than just thicker?
The researchers scoured three databases up to February 2024 and sourced studies that looked at longer and shorter muscle length training. The studies included in the review involved healthy adults, lasted a minimum of four weeks, and measured muscle size and fascicle length before and following training. The review included 120 mostly untrained participants, and the most widely studied muscle was the vastus lateralis, which is the largest of the four quadriceps muscles of the thigh.
The results
Here are the results of this in-depth review:
- Most studies in the review revealed that training at longer muscle lengths resulted in more significant muscle size enhancements than resistance training at shorter muscle lengths. This was especially true in the parts of the muscles closer to the joints.
- The researchers reported some increases in the fascicle angle with longer muscle length training, which indicates that this type of training could also enhance muscle thickness as well as length.
- The fascicle length is the term for the length of muscle fibres within a muscle. Some studies revealed that training at a longer muscle length prompted a greater increase in fascicle length, though these enhancements were smaller overall.
- Training at longer muscle lengths seems more efficacious for amplifying muscle size and promoting longitudinal muscle growth than shorter muscle length training.
It’s important to note that there were some mixed findings and measurement issues, so more research is needed to come to clearer conclusions.
In summary
While we need more research, hearing about this review makes me want to reach the bottom of that pull-up or the deeper part of that squat before returning to the starting position. It makes sense that putting your muscles through a fuller range of motion and the longer or elongated part of the movement could yield more longitudinal muscle growth. Previous research also indicates that training lengthened partial reps and the full range of motion delivers similar results when it comes to building muscle size and power.
