The papers, and what they actually say

Williams TD, Tolusso DV, Fedewa MV, Esco MR. Comparison of periodized and non-periodized resistance training on maximal strength: a meta-analysis. Sports Medicine. 2017;47(10):2083–2100.

Finding. Across 18 studies and 81 effects, periodized training beat non-periodized training for 1RM strength (ES = 0.43, 95% CI 0.27–0.58). Undulating models did best; longer studies and higher frequency helped.

How Rhyno uses it. This is why Rhyno waves intensity inside every 4-week block instead of adding weight every week.

Ramírez-delaCruz M, Bravo-Sánchez A, Esteban-García P, Jiménez F, Abián-Vicén J. Effects of plyometric training on lower body muscle architecture, tendon structure, stiffness and physical performance: a systematic review and meta-analysis. Sports Medicine – Open. 2022;8:40.

Finding. 32 studies: plyometric training increased tendon stiffness (SMD 0.55), muscle thickness (0.59) and fascicle length (0.51), and improved jumping (0.61) and strength (0.57).

How Rhyno uses it. The evidence base for the elastic block. Springiness is trainable tissue quality, not a gift you lose at 40.

van Dyk N, Behan FP, Whiteley R. Including the Nordic hamstring exercise in injury prevention programmes halves the rate of hamstring injuries: a systematic review and meta-analysis of 8459 athletes. British Journal of Sports Medicine. 2019;53(21):1362–1370.

Finding. Programmes including the Nordic hamstring curl cut hamstring injury risk roughly in half (risk ratio 0.49, 95% CI 0.32–0.74).

How Rhyno uses it. One of the few 'insurance policy' exercises with real outcome data. It is in the program — with regressions shown, because full Nordics are brutal.

Behm DG, Blazevich AJ, Kay AD, McHugh M. Acute effects of muscle stretching on physical performance, range of motion, and injury incidence in healthy active individuals: a systematic review. Applied Physiology, Nutrition, and Metabolism. 2016;41(1):1–11.

Finding. Long static stretching before training costs performance (−4.6% at ≥60 s per muscle group); dynamic stretching helps slightly; a warm-up that stretches then moves shows no clear performance cost.

How Rhyno uses it. This is why the 12-minute primer is movement, not floor stretching — and why long holds live at the end of the session.

Zourdos MC, Klemp A, Dolan C, et al. Novel resistance training-specific rating of perceived exertion scale measuring repetitions in reserve. Journal of Strength and Conditioning Research. 2016;30(1):267–275.

Finding. RPE anchored to repetitions in reserve (RIR) tracked bar velocity closely in experienced lifters (r = −0.88), and less closely in novices (r = −0.77).

How Rhyno uses it. Rhyno uses RIR as the effort dial — and it works better the more training history you have, which is the point.

McGill SM, Karpowicz A. Exercises for spine stabilization: motion/motor patterns, stability progressions, and clinical technique. Archives of Physical Medicine and Rehabilitation. 2009;90(1):118–126.

Finding. The curl-up, side bridge and bird dog produce meaningful trunk-muscle activation at low spine load, and are progressable by changing leverage rather than adding compression.

How Rhyno uses it. Small lab study (8 healthy men). It is a biomechanics rationale, not an outcome trial — which is exactly how Rhyno treats it: short holds, never to failure.

Kjaer M. Role of extracellular matrix in adaptation of tendon and skeletal muscle to mechanical loading. Physiological Reviews. 2004;84(2):649–698.

Finding. Tendon and the surrounding connective-tissue matrix are living, mechanically responsive tissue: loading changes collagen turnover, cross-linking and stiffness — on a much slower timescale than muscle.

How Rhyno uses it. The reason connective tissue gets its own block every session, and the reason progress is deliberately slow.

Wolf M, Androulakis-Korakakis P, Fisher JP, Schoenfeld BJ, Steele J. Partial vs full range of motion resistance training: a systematic review and meta-analysis. International Journal of Strength and Conditioning. 2023;3(1).

Finding. Full or long range of motion was at least as good as partials for strength, size, power and speed; differences were trivial to small, and adaptations were partly specific to the range you train.

How Rhyno uses it. Honest reading: 'train the end range' is justified by specificity, not by a big hypertrophy edge. Rhyno trains full range and adds loaded end-range work on top.

Stöggl T, Sperlich B. Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training. Frontiers in Physiology. 2014;5:33.

Finding. Nine weeks of polarized training (most volume easy, a little very hard, almost nothing in the middle) produced the largest gains in VO₂peak and time to exhaustion.

How Rhyno uses it. Trained endurance athletes, 9 weeks. It is the reason Rhyno's aerobic day is deliberately easy instead of a fifth hard session.

Düking P, Zinner C, Trabelsi K, et al. Monitoring and adapting endurance training on the basis of heart rate variability monitored by wearable technologies: a systematic review with meta-analysis. Journal of Science and Medicine in Sport. 2021;24(11):1180–1192.

Finding. HRV-guided training had a medium effect on submaximal physiology but small, non-significant effects on performance and VO₂peak — with fewer non-responders.

How Rhyno uses it. Why Rhyno logs readiness for charts but never lets an algorithm rewrite today's prescription.

Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. The American Journal of Clinical Nutrition. 2017;105(1):136–143.

Finding. Gelatin plus vitamin C taken an hour before short, frequent loading raised a blood marker of collagen synthesis, and serum from those subjects increased collagen content in engineered ligaments.

How Rhyno uses it. Surrogate markers, not tendon outcomes in trained adults. Rhyno takes only the training implication from it: brief, frequent, repeated loading of tissue beats one heroic session.

Rio E, Kidgell D, Purdam C, et al. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy. British Journal of Sports Medicine. 2015;49(19):1277–1283.

Finding. A single bout of heavy isometric holds cut tendon pain by 6.8/10 for at least 45 minutes and raised maximal voluntary contraction by ~19%.

How Rhyno uses it. Six volleyball players. Striking effect, tiny sample. Isometrics are in the program because they are low-cost and low-risk, not because this proves they must be.

Volk NR, Wambach JM, Bruder O, Meyer T, Kellmann M, et al. Recovery from eccentric squat exercise in resistance-trained young and master athletes with similar maximum strength. Frontiers in Physiology. 2021;12:665204.

Finding. Masters lifters (~52 y) did not reach higher fatigue levels or recover more slowly than young lifters (~22 y) of similar relative strength. Cold water immersion plus compression did not speed real recovery.

How Rhyno uses it. 16 men. Age is not automatically a recovery penalty — training history is. Rhyno manages fatigue with scheduled unloads, not ice baths.

Wilke J, Schleip R, Yücesoy CA, Banzer W. Not merely a protective packing organ? A review of fascia and its force transmission capacity. Journal of Applied Physiology. 2018;124(1):234–244.

Finding. Cadaver and animal work shows real myofascial force transmission between synergists and along muscle-fascia chains; early human trials show non-local exercise effects.

How Rhyno uses it. Read the fine print: how much force transfers, and how much of the 'remote effect' is neural, is still contested. Rhyno trains long chains because it is cheap and plausible — it does not claim to 'fix your fascia'.