I Spent $40,000 To Prove Them Wrong (My NEW Study)

About this video

• Video Title: I Spent $40,000 To Prove Them Wrong (My NEW Study)
• Channel: Jeremy Ethier
• Speakers: Jeremy Ethier
• Duration: 18:46

Overview

This video details a comprehensive study costing $40,000 that investigated the effectiveness of emphasizing muscle stretch versus muscle squeeze in exercises for muscle growth. The study aimed to resolve conflicting information in the fitness community regarding the importance of the stretch phase.

Key takeaways

• The Stretch Hype: The fitness community has become overly focused on maximizing muscle stretch during exercises, with the belief that this leads to superior muscle growth.
• Previous Research: Studies from the 1970s onwards indicated benefits of stretching muscles for growth, with some experiments showing significant gains from loaded stretching and exercises that emphasize the stretch.
• Study Design: A year-long study was conducted using custom machines and MRI scans to compare muscle growth from exercises that were made hardest in the stretch versus those made hardest in the squeeze. A within-subjects design was employed, where each participant trained one side of their body for stretch focus and the other for squeeze focus.
• Unexpected Results: The study found no significant difference in muscle growth between the stretch-focused and squeeze-focused training for the tested muscles (chest, side delts, rear delts, glutes).
• Nuances of Stretch: The video clarifies that the "stretch" concept has three components: the degree of stretch (greater for bi-articular muscles), the range of motion (full ROM is crucial), and the resistance profile (emphasizing the stretch doesn't necessarily yield more growth if full ROM is maintained).
• Muscle Specificity: While most tested muscles showed similar growth, bi-articular muscles (hamstrings, quads, calves, triceps) and potentially lats may still benefit more from exercises that heavily emphasize the stretch.
• Practical Implications: The findings suggest flexibility in exercise selection; as long as training is hard and full range of motion is used, various exercises can be effective for muscle growth, which is beneficial for those working around injuries or equipment limitations.