Key takeaways

  • Stability is King: The more stable an exercise (e.g., using machines or external bracing), the better the nervous system can recruit high-threshold motor units and produce force for hypertrophy.
  • The Two-Exercise Rule: To fully stimulate a muscle, select one exercise that emphasizes the lengthened position and (if volume allows) a second that emphasizes the shortened position.
  • Joint Actions: Align exercises with the anatomical functions of the target muscle. Avoid active insufficiency (training a muscle when it is too short to produce force) unless isolating specific heads.
  • Resistance Profiles: Choose equipment (machines, cables, or free weights) that provides a resistance profile matching the muscle’s strength curve, ensuring tension remains high where it matters most.

References

# Reference Identifier
[1] Behm DG, Anderson KG. The role of instability with resistance training. J Strength Cond Res. 2006;20(3):716–722. doi: 10.1519/R-18475.1
[2] Willardson JM. Core stability training: applications to sports conditioning programs. J Strength Cond Res. 2007;21(3):979–985. doi: 10.1519/R-20255.1
[3] Cresswell AG, Thorstensson A. Changes in intra-abdominal pressure, trunk muscle activation and force during isokinetic lifting and lowering. Eur J Appl Physiol Occup Physiol. 1991;63(5):345–352. doi: 10.1007/BF00364462
[4] Maeo S, Huang M, Wu Y, et al. Greater hamstrings muscle hypertrophy but similar damage protection after training at long versus short muscle lengths. Med Sci Sports Exerc. 2021;53(4):825–837. doi: 10.1249/MSS.0000000000002523
[5] Pedrosa GF, et al. Partial range of motion training elicits favorable improvements in muscular adaptations when carried out at long muscle lengths. Eur J Sport Sci. 2022;22(8):1250–1260. doi: 10.1080/17461391.2021.1927199