REF-1160 · Lum & Barbosa, 2019 · International Journal of Sports Medicine · Paper · PubMed

How much isometric work, and how hard?

A narrative review (no pooled data) suggests 70-75% MVC, 3-30 s holds, >80-150 s a session for size, and 80-100% MVC, 1-5 s, 30-90 s a session for maximal strength.

C+thin evidenceMeasured on recreational to highly trained athletes

Lum and Barbosa summarise isometric strength training (IST) studies on what drives strength gains and whether IST transfers to sport. They state that IST causes less fatigue than dynamic strength training, gives greater strength at the trained joint angle, and has benefited running, jumping and cycling performance.

They suggest four uses: keeping neuromuscular gains while avoiding fatigue, strengthening a weak joint position in a movement, training sports that are mainly isometric, and training around injuries that limit mobility.

Their doses: for hypertrophy 70-75% MVC, 3-30 s per contraction, more than 80-150 s of total contraction per session, for more than 36 sessions; for maximal strength 80-100% MVC, 1-5 s per contraction, 30-90 s per session, at several joint angles or at the targeted one; ballistic contractions to maximise rate of force development.

Included studies

Narrative summary of IST studies; the abstract gives no search strategy, number of studies or populations.
Isometric type implied: overcoming (pushing) contractions; holding (yielding) contractions are not mentioned in the abstract.

Key Results

GoalIntensityContraction lengthVolume per sessionDuration
Hypertrophy70-75% MVC3-30 s, sustained> 80-150 s total contraction> 36 sessions
Maximal strength80-100% MVC1-5 s30-90 s total contractionnot given; multiple or targeted joint angles
Rate of force developmentnot givenballisticnot givennot given
Qualitative claims (abstract): IST induces less fatigue than dynamic strength training; IST gives superior joint-angle-specific strength; IST benefited running, jumping and cycling.

Mechanisms

Authors' interpretation: angle-specific strength and lower fatigue are the features that make IST useful; mechanisms are not stated in the abstract.
Inference: the hypertrophy prescription (sustained holds, high total contraction time) matches the sustained-vs-explosive contrast in REF-1161, where volume under load drove muscle growth and peak load drove maximal strength.

Practical Application

How much isometric work, and how hard? A narrative review (no pooled data) suggests 70-75% MVC, 3-30 s holds, >80-150 s a session for size, and 80-100% MVC, 1-5 s, 30-90 s a session for maximal strength.
Treat these as the authors' starting doses: the abstract does not trace them to specific trials, and the size dose is prescribed for more than 36 sessions.
Base's practice, not the paper's: use isometric holds when an athlete needs strength stimulus with little fatigue or little joint movement (a heavy race block, a sore joint, travel), and return to dynamic heavy lifting when possible (SYNTH-43, SYNTH-44).
For a sticking point, train the angle; for general strength, train several angles. That angle advice agrees with the controlled trial in REF-1159; how widely gains spread depends on muscle length (REF-1158).
The claim that isometric training helps running and cycling is the authors' summary; check the trials before relying on it (for runners, REF-801 pooled only three isometric studies; for cycling, the one controlled trial in the base was published after this review, in elite track sprinters, and beat usual heavy lifting on power per kilogram but not on absolute power, REF-1182, B).

Limitations

Narrative review: no stated search, selection or appraisal in the abstract; the dosing ranges cannot be traced to specific trials from the abstract alone.
Read from the abstract only: populations, study counts and the evidence for the running and cycling claims were not seen.
The 80-100% MVC rule for maximal strength sits awkwardly with REF-1158, which found intensity explained little of the maximal-force gain across studies.
Funding: not stated in the abstract. Conflicts of interest: none declared (PubMed record).
Revision 2026-10-20: pointer to REF-1182 (Kordi 2020, B), the only controlled trial of isometric training in cyclists in the base, published after this review, added to Practical and Cross-References. Level unchanged.
How this entry was checked and changed
Why this level

narrative review without systematic method; the dosing numbers are the authors' synthesis, not pooled estimates; from the abstract (the only open copy sits behind a bot-check page and was not read)