Science
The research the BLOCKS assistant answers from: 1,118 studies and 81 guides, each graded for how strong the evidence is and who it was measured on, with a link to the original paper.
1,118 entries
B+Does a mid-thigh pull show strength in movement?In 47 correlational studies, IMTP force tracked 1RM squat (r 0.71-0.97) and related to jumps and sprints, explaining 12-94% of variance. A proxy, not a 1RM; no endurance data.Lum 2020B+Is the mid-thigh pull a trustworthy strength test?Across 16 studies peak force repeated well (median ICC 0.96, CV 4.9%). Mostly team-sport athletes; standardise the position. A change under ~5% is noise; only clearly larger ones count.Grgic 2022A-Does an isometric hold before a jump help?Over 25 studies it raised jump height slightly vs no primer (ES 0.35), like a heavy dynamic set; no clear effect on strength or power (few studies). Low certainty; untested for endurance.He 2026BIs holding a weight harder than pushing a wall?At 80% MVC in 10 adults, a held elbow position stayed still 19 s vs 41 s when pushing; total time at that force differed less (50 vs 59 s). One small arm study.Schaefer & Bittmann 2017BPush or hold for isometrics?In 10 adults over 6 weeks, pushing at 70% MVC raised concentric and eccentric strength; holding a load did not, but grew the quadriceps more. Mostly small effects; a first signal only.Lum 2026B+Can isometric holds replace full-range lifting for quad size?In 23 trained lifters over 6 weeks, long-length isometric knee extension grew the front thigh about as much as full-range reps (difference -0.20 cm, uncertain).Varovic 2025B+Explosive or slow isometric reps?In untrained men over 12 weeks, 3-s holds at 75% raised max strength 23% and quad size 8.1%; 1-s fast-and-hard reps gave 17% and alone improved force in the first 100 ms.Balshaw 2016C+How much isometric work, and how hard?A narrative review (no pooled data) suggests 70-75% MVC, 3-30 s holds, >80-150 s a session for size, and 80-100% MVC, 1-5 s, 30-90 s a session for maximal strength.Lum & Barbosa 2019B+Does an isometric hold only strengthen that one angle?Knee holds at 65 degrees for 4 weeks gave +12% there, +5 to 11% at nearby angles and nothing 30 degrees deeper. Untrained men, one leg; train near the angle you need.Lanza 2019A-Long or short muscle length for isometric holds?In 26 small trials in non-athletes, long-length holds grew muscle faster (1.16 vs 0.47%/week, 3 studies) and spread strength to more angles; over 9 studies the gap shrank (0.88 vs 0.61).Oranchuk 2019BIsometric and plyometric training, added twice a week for 6 weeks, both improved 2.4-km time-trial time, maximal aerobic speed, jump height and isometric mid-thigh pull force more than a bodyweight circuit in endurance runners; the authors' claim that isometrics improved running economy more rests on a time effect, not a significant group differenceLum 2023BHeavy isometric calf training lowered the energy cost of running about 4% in recreational runners14 weeks of 90% MVC isometric plantarflexion (5 × 4 × 3 s, 3-4×/week) raised plantarflexor strength 10% and Achilles stiffness 31%, and the soleus then shortened at more efficient speeds; the fall in…Bohm 2021BHeavy isometric calf training made running about 4% cheaper14 weeks of 90% MVC isometric plantarflexion (5 × 4 × 3 s, 4×/week) raised plantarflexor strength ~7% and triceps surae tendon stiffness ~16% and cut the oxygen cost of running at 3.0 and 3.5 m/s ~4%…Albracht & Arampatzis 2013BHold length matters for tendon, not for strength12 weeks of isometric knee extension at 70% MVC with matched volume: 20-s holds and 1-s pulses built the same strength (+34% vs +32%) and quadriceps volume (+7.6% vs +7.4%), but only the 20-s holds…Kubo 2001BAchilles tendon adaptation has a strain threshold14 weeks of isometric plantarflexion at matched frequency and volume stiffened the tendon, raised its modulus and thickened it regionally only in the leg loaded to ~4.6% tendon strain (90% MVC), not…Arampatzis 2007A-Healthy lower-limb tendons stiffen with loading (stiffness SMD 0.74, modulus 0.82, cross-section only 0.22 across 61 studies), the gain is mostly a material change, resistance training works best, and protocols that reached high tendon strain (~5%) beat low-strain ones (~3%)A contrast that rests on three high-strain intervention groups from the few studies that measured strainLazarczuk 2022A-Effectiveness and safety of isometric resistance training in adults with high blood pressureAcross 24 RCTs (mostly handgrip, 4 × 2 min at 30% of maximum) office BP fell 6.97/3.86 mmHg against controls with no rise in adverse events (7 minor vs 1, about one per 38,444 bouts), but every trial…Hansford 2021A-Exercise training and resting blood pressure, a network meta-analysis of 270 RCTs (15,827 adults)Isometric exercise training lowered resting BP by 8.24/4.00 mmHg against no-exercise controls and ranked first of five modes for systolic pressure (SUCRA 98.3%); by sub-mode, wall squat −10.47/−5.33…Edwards 2023A-Effectiveness of isometric exercise in tendinopathyAcross 10 small RCTs (294 participants, five tendon sites) isometrics were not superior to isotonic exercise for pain, either straight after a session (3 patellar trials pooled, p = 0.19) or over up…Clifford 2020BAcute sensory and motor response to 45-s heavy isometric holds for the plantar flexors in Achilles tendinopathyFive 45-s calf holds at 70% MVC gave no immediate pain relief (functional pain 4.2 → 4.9 of 10, not significant, in the 9 of 16 who had pain to test), no change in pressure pain, and the most painful…O'Neill 2019B+Isometric exercise and pain in patellar tendinopathy, a pre-registered crossover replication of Rio 2015One session of 5 × 45-s quadriceps holds at 70% MVIC was no better than dynamic leg extensions: pain on the decline squat fell only 0.9 of 10 across both, had drifted back by 45 min, and 4 of 20…Holden 2020BIn-season jumping athletes with patellar tendinopathy who kept training and competing: 4 weeks of isometric or isotonic leg exercise, 4 sessions a week, both reduced decline-squat pain, with no difference between them (median change 2.5 vs 3.0 of 10, p = 0.208); n=29 randomised, about 19 analysedvan Ark 2016B+Isometric contractions are more analgesic than isotonic contractions for patellar tendon pain in-seasonOver 4 weeks of 4 sessions a week, isometric leg-extension holds eased decline-squat pain within each session more than isotonic leg extensions (P < 0.002), both programmes reduced pain, n=20; the…Rio 2017B+Strength training improves running economy durability and fatigued high-intensity performance in well-trained male runners10 weeks of twice-weekly heavy lifting plus jumps cut the economy drift over a 90-min run (4.7% to 2.1% from minute 15 to 90) and lengthened a run to exhaustion straight after it by 35%, while fresh…Zanini 2025B-Why people gain so differently from the same resistance programmeSummary of the 2025 Jyväskylä conference by the leading groups: the training variables matter (about 12 sets per muscle a week, at least 60 s rest and 2 min on multi-joint lifts, no more than 2 reps…Roberts 2026BStrength back after short disuse10 days with one leg unloaded cost young men 29% of quadriceps force and 4% of muscle volume; nine sessions of 3 × 10 at 70% 1RM over 21 days restored the force and took volume above baseline, while…Franchi 2025C+Minimal-dose resistance exercise for people who do not liftOne session a week, one set per exercise, daily "snacks", practising a maximal lift or a few maximal eccentric contractions each raise strength over doing nothing; once-weekly and single-set training…Nuzzo 2024A-Resistance-training volume in adults aged 60 and overAcross 151 randomised trials the lowest weekly volume ranked most effective for the timed up-and-go, 6-min walk, lean mass and leg muscle size, moderate and high volume for leg strength, and only…Radaelli 2025A-Heavy resistance training at retirement age: one supervised year of heavy lifting kept isometric leg strength at its baseline three years after the programme ended, while controls lost 7%But leg power, grip strength and leg lean mass fell in every group alikeBloch-Ibenfeldt 2024B+Rise and fall of physical capacity in a general population followed from 16 to 63Every capacity peaked by 36 and fell 30-48% by 63, the yearly loss rising from under 1% to about 2%, while the spread between people grew 3- to 25-fold and being active at 16, or becoming active…Westerståhl 2025BI'm stuck in bed for two weeks — how much leg muscle will I lose?In 12 healthy young men kept in strict bed rest for 14 days, thigh muscle volume fell 5% on MRI (7.1 → 6.7 L), leg lean mass 5% on DXA (10.2 → 9.7 kg) and thigh cross-sectional area 6% on CT, with…Fuchs 2025BI can only train once a week — or once a fortnight — for 3 months. Will I keep what I built?Once a week, yes; once a fortnight, partly. The same full session every 7 days held leg strength, quadriceps size and aerobic power for 12 weeks; every 14 days, by week 12, about half the size and…Mpampoulis 2024A-I'm over 60 — if I stop training for a few months, is the work wasted?No, but it is not banked either: older adults who had trained still did better than never-trained peers after 4-36 weeks off (ES 0.88), less so the older they were (β −0.06 per year), and the…Buendía-Romero 2025BI spent a week in bed — how long before I'm back to normal?Plan at least 2-4 weeks of progressive rebuilding with strength work in it — the authors' advice after up to 28 days in bed, possibly longer after illness or injury. No study has measured real…Spiering 2023B+I took 3 weeks off — how much did I lose?Some aerobic capacity, not most of it: in trained endurance athletes who stopped completely, VO2max was about 4-7% lower after 12-21 days, about 10% after 5 weeks and 13-20% after about 8 weeks…Barbieri 2024BSex differences in durability following heavy intensity cycling exercise in trained athletesAfter 90 min at 110% of GET on water only, power at the first threshold fell 16% in men and 2% in women, while peak power, VO2peak and neuromuscular function fell alikePastorio 2026B+Host-diet-gut microbiome interactions influence human energy balance: a randomized clinical trialCorbin 2023B+Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food IntakeHall 2019BPostprandial energy expenditure in whole-food and processed-food meals: implications for daily energy expenditureBarr & Wright 2010BRole of Nonexercise Activity Thermogenesis in Resistance to Fat Gain in HumansLevine 1999