The Claim
In resistance-trained individuals, isometric training at long muscle lengths and full range of motion isotonic training result in similar overall quadriceps hypertrophy as measured by summed anterior thigh muscle thickness changes over a 6-week intervention with twice-weekly sessions, with isometric training producing a slightly greater effect at the proximal anterior thigh site.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
In people who regularly lift weights, training with static muscle contractions at stretched muscle positions and training with full-range dynamic movements produce similar increases in quadriceps muscle size over six weeks, though static training leads to slightly more growth in the upper part of the front thigh.
See the scientific wording
In resistance-trained individuals, isometric training at long muscle lengths and full range of motion isotonic training produce similar overall quadriceps hypertrophy, as measured by summed anterior thigh muscle thickness changes over a 6-week intervention with twice-weekly sessions, though isometric training may have a slightly greater effect at the proximal anterior thigh site.
When the thigh muscle is stretched and held under tension, the muscle fibers experience greater force per area, which triggers more protein building in the upper part of the muscle. When the muscle moves through a full range of motion, the same total amount of protein building happens across the whole muscle, but the stretched position adds a little extra building at the top.
What the research says
1 studyFor people who already lift weights, holding a muscle in a stretched position works about as well as moving through a full range of motion to build muscle in the front of the thigh—though holding might help a tiny bit more near the top of the thigh, but we’re not totally sure yet.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.