Sports science, distilled.
Summaries and analysis of key research papers in sports science, velocity-based training, and performance measurement.
Inter-Individual Response Variability: Why Same Program Produces Different Results
481 people did the identical 20-week program; VO2max changes ranged from -6% to +100%. The genetic and lifestyle factors behind high vs low responders.
Muscle Fiber Type Shifting: Can Training Convert IIx to IIa?
Serial biopsy data show 14 weeks of heavy training shrank Type IIx fibers from 9% to 2% of the vastus lateralis. Here is the mechanism and reversibility.
Optimal Rep Range for Hypertrophy: Why the 8-12 Rule Is Incomplete
The hypertrophy continuum reviewed: why reps from 5 to 30 build muscle equally near failure, what actually caps growth, and how to pick your rep range.
Resistance Training and Longevity: Does Strength Training Reduce Mortality?
Large epidemiological studies link resistance training to a 15-23% drop in all-cause mortality risk. Here is the dose-response data and likely mechanisms.
Single vs Multi-Joint Exercise: Hypertrophy and Strength Comparison
Does isolation work build more muscle than compound lifts alone? A 14-trial meta-analysis found extra gains in only 4 comparisons - here's when it helps.
Strength Training Hormonal Hypothesis: Do Acute Hormones Drive Growth?
High-rep training was long justified by post-workout T and GH spikes. Newer trials show local mechanical and metabolic signals predict growth far better.
Stretch-Mediated Hypertrophy: Does Training at Long Lengths Boost Growth?
A 2023 meta-analysis of 19 RCTs found training at long muscle lengths produced 34% greater hypertrophy than short-length work. Here's the mechanism.
Is Training to Failure Necessary? What Latest Research Says
A 2022 meta-analysis pooling 15 studies and 391 lifters found no significant hypertrophy edge from failure training over reps-in-reserve approaches.
Concurrent Training Molecular Interference: AMPK vs mTOR Truth
Running before lifting can quietly sabotage hypertrophy at the molecular level. Here's how AMPK-mTOR interference works, and the sequencing that limits it.
IMU Sensor Validity for Barbell Velocity Measurement: Systematic Review
A 23-study review found IMU sensors match lab-grade linear transducers within 0.01-0.04 m/s. Where that accuracy holds, and where it breaks down.
Minimum Effective Volume for Hypertrophy: How Little Can You Train?
Just 5 sets weekly triggered significant hypertrophy, though 10+ sets grew muscle 35% faster. See the dose-response curve and where the real payoff sits.
Velocity Loss Thresholds and Training Outcomes: 10% vs 20% vs 30%
The 2017 Pareja-Blanco study pitted 10%, 20%, and 30% velocity loss thresholds head-to-head, revealing which built strength and which just caused fatigue.