Lengthened state eccentric training increases the size of certain hamstring muscles that help extend the hip more than Nordic hamstring training, while Nordic hamstring training increases the size of...
Mechanism
Synthesis from 1 study
When you bend your hip and slowly bend your knee, the muscles that cross both joints stretch tightly and grow bigger. When you keep your hip straight and bend your knee, those muscles don’t stretch as much, so other muscles that only cross the knee do more work and grow bigger instead.
Most probable mechanism
When the hip is bent during eccentric knee flexion, the muscles that cross both the hip and knee are stretched tightly, causing them to grow more. When the hip is straight, those same muscles are not stretched as much, so other muscles that only cross the knee take over and grow instead.
Hip flexion during eccentric knee flexion elongates biarticular hamstring muscles (biceps femoris long head, semitendinosus, semimembranosus) across both hip and knee joints, placing them under high mechanical tension at long muscle lengths
High mechanical tension at long muscle lengths activates mechanotransduction pathways that increase muscle protein synthesis and inhibit protein breakdown, leading to sarcomere addition in series and radial growth
Increased protein synthesis results in greater volume gains in biarticular hamstrings that span both hip and knee joints
Hip extension during Nordic hamstring training reduces passive stretch on biarticular hamstrings, shifting mechanical load to monoarticular knee flexors (biceps femoris short head, sartorius, gracilis, popliteus) that are not stretched across the hip
Eccentric contractions performed under high load by monoarticular knee flexors stimulate localized muscle protein synthesis and hypertrophy in these muscles
High eccentric forces transmitted through the biceps femoris long head during hip-flexed training increase mechanical strain on its proximal aponeurosis, triggering fibroblast activity and collagen remodeling that enlarges the aponeurosis
Evidence from Studies
Supporting (1)
Community contributions welcome
Hamstrings Hypertrophy Is Specific to the Training Exercise: Nordic Hamstring versus Lengthened State Eccentric Training
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.