Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 42647753

Comparing the Effects of Push and Hold Isometric Training on Strength and Musculotendinous Adaptations: A Within-Subject Randomized Controlled Trial.

Danny Lum·Dustin J Oranchuk·Siow E Chen·Pui Wah Kong
View original source ↗Export metadata ↓

Abstract

Lum, D, Oranchuk, DJ, Chen, SE, and Kong, PW. Comparing the effects of push and hold isometric training on strength and musculotendinous adaptations: A within-subject randomized controlled trial. J Strength Cond Res 40(9): 1050-1058, 2026-Despite recent interest in delineating pushing (PIMA) and holding (HIMA) isometric muscle actions, training-induced adaptations have not been examined. As such, we compared the strength and morphological adaptations between PIMA and HIMA training. Twenty limbs across 10 adults (5 men, 5 women, age: 31.4 &#xb1; 6.5 years) were randomly assigned to PIMA or HIMA conditions and underwent 12 training sessions over 6 weeks. PIMA required subjects to exert force against a fixed lever while the HIMA limb maintained a set joint angle while resisting an isotonic lever. During each contraction, subjects had to exert force at 70% of maximal voluntary contraction for 20 seconds at an 80&#xb0; knee angle, for 4-6 repetitions. Subjects completed isometric, concentric, and eccentric knee extension assessments for both limbs before and after the intervention. Pre- and postintervention ultrasound scans were performed to determine quadriceps muscle architecture and patellar tendon thickness. Increased isometric torque was found following both conditions (p < 0.05, g = 0.30-0.36), while concentric (p < 0.05, g = 0.31) and eccentric (p < 0.01, g = 0.50) torque only increased following PIMA. Both conditions increased muscle thickness (p < 0.05, g = 0.27-0.88) and vastus lateralis fascicle length (p < 0.05, g = 0.20-0.31). Only HIMA increased patellar tendon thickness (p < 0.05, g = 0.12). The increase in total quadriceps (p < 0.05, g = 0.46) and especially rectus femoris (p < 0.05, g = 1.44) thickness was greater in HIMA. The results suggest that PIMA may be more effective at improving strength, while HIMA may be superior for inducing morphological adaptations. Larger sample sizes and more ecologically valid training programs are warranted to further elucidate potential differences between different isometric types.

Explore related subjects

HumansFemaleAdaptation, PhysiologicalIsometric ContractionMaleMuscle StrengthAdultResistance TrainingQuadriceps MusclePatellar LigamentUltrasonographyTorqueYoung Adultisotonicmuscle architectureovercoming isometricquasi-isometrictendonyielding isometricJournal ArticleRandomized Controlled TrialComparative Study

Keep this discovery

BibTeXRIS

Danny Lum, Dustin J Oranchuk, Siow E Chen, Pui Wah Kong. 2026-07-15. Comparing the Effects of Push and Hold Isometric Training on Strength and Musculotendinous Adaptations: A Within-Subject Randomized Controlled Trial.. https://doi.org/10.1519/jsc.0000000000005475

Cite the original work for its findings. Save a collection to share your selection of sources.

Discover connections

Journal Article; Randomized Controlled Trial; Comparative Study resourceAdaptation, Physiological subjectAdult subjectComparative Study subjectFemale subjectHumans subjectIsometric Contraction subjectJournal Article subjectMale subjectMuscle Strength subjectPatellar Ligament subjectRandomized controlled trials study

Connections use source metadata and explicit phrase matches, not verified experimental comparisons.

KEEP EXPLORING

Related citations

PubMed2026

Transcriptomic insights into thermal stress reveal physiological trade-off between thermal stress adaptation and reproductive investment in Spodoptera litura.

Spodoptera litura, a highly polyphagous lepidopteran pest, poses a major threat to agricultural productivity due to its remarkable adaptability to diverse environmental conditions. Although heat stress is known to trigger transcriptional reprogramming in insects, the molecular mechanisms underlying thermal stress responses in S. litura remain poorly understood. In the present study, fourth-instar larvae were exposed to acute heat stress (44&#xa0;&#xb0;C) and compared with control conditions (27&#xa0;&#xb1;&#xa0;1&#xa0;&#xb0;C) to investigate heat-induced transcriptional alterations affecting physiology and reproduction. High-quality RNA-Seq data achieved more than 80% mapping efficiency, with a total of 15,782 transcripts were identified. Transcriptome analysis of S. litura larvae showed 323 differentially expressed genes (DEGs), of which 262 genes were significantly upregulated and 61 were downregulated in heat-stressed larvae compared to the control group. The DEGs were associated with stress response, reproduction, signalling, proteostasis, detoxification, oxidative stress, metabolism, development, and chromatin regulation. Heat shock proteins genes, including HSP70, HSP90, and HSP27, together with co-chaperones such as TRET-1, STIP1, and Starvin, were strongly upregulated, indicating enhanced cellular protection against protein damage and oxidative stress under heat stress. Conversely, key reproductive and cell cycle-related genes, including BARR, CAPD2, FEO, CDK2 and MORULA, were significantly downregulated, suggesting reproductive impairment and developmental arrest. RT-qPCR validation corroborated the RNA-Seq findings, demonstrating a heat-induced physiological trade-off that prioritizes survival over reproduction. Consistent with these molecular responses, heat-stressed insects exhibited marked reproductive impairment, including significant reductions in gonadosomatic index, eupyrene sperm bundle count, mating frequency, mating success, female calling behaviour, copulation duration, fecundity, and egg fertility. Collectively, these findings provide comprehensive insights into the molecular basis of thermal adaptation in S. litura and demonstrate that acute heat stress compromises reproductive fitness while activating conserved stress-response pathways that promote short-term survival.

Animals↗
PubMed2026

Molecular adaptation of caspase genes to salinity stress in the tropical sea cucumber Stichopus monotuberculatus: A comparative analysis across echinoderms.

Apoptosis is an essential physiological process that plays a critical role in development and tissue homeostasis. Caspases, as central regulators of apoptosis, are crucial in controlling inflammation and cell death. In this study, we investigated the caspase gene family in Stichopus monotuberculatus to explore their potential roles in salinity stress adaptation. Five caspase genes were identified from the genome of S. monotuberculatus, including Smcaspase3, Smcaspase6, Smcaspase8a, Smcaspase8b, and Smcaspase8c. Phylogenetic analysis revealed that these Smcaspase genes clustered into distinct caspase subfamilies and showed high conservation with homologs from other echinoderms and representative vertebrates. Conserved motif and gene structure analyses showed relatively similar structural patterns within each clade, whereas divergence was observed among different subfamilies. Promoter analysis identified numerous cis-acting elements related to gene regulation, immune response, and growth and development. Expression profiling under salinity stress showed that Smcaspase8a was significantly upregulated, particularly under prolonged stress, whereas the other genes exhibited limited transcriptional responses. Our findings highlight caspase function in salinity stress and provide the foundation of molecular salinity adaptation mechanisms in S. monotuberculatus.

Animals↗
PubMed2026

Effects of Time-Based and Distance-Based Repeated Sprint Training on Physical and Physiological Adaptations in Collegiate Basketball Players.

PURPOSE: This study aimed to compare the effects of time-based (TB) and distance-based (DB) repeated-sprint training (RST) on athletic performance adaptations in collegiate basketball players during preseason and to examine whether the 2 training prescriptions produce different levels of homogeneity in the magnitude of individual adaptations. METHODS: Thirty young male basketball players (age = 21.3 [1.4]&#xa0;y) were randomly and equally assigned to 3 groups (n = 10): DB-RST, TB-RST, and an active control group. Participants completed a 7-week RST program performed 3 times per week, consisting of 4 sets of 4 to 9 repetitions per session. The DB-RST group completed each sprint by covering a fixed 35-m distance, whereas the TB-RST group performed each sprint maximally for a fixed 5-second duration. Performance assessments including countermovement vertical jump, 20-m sprint, Illinois change-of-direction speed, reactive strength index, Wingate anaerobic power, and cardiorespiratory fitness were conducted before and after the 7-week training period. RESULTS: Both training groups demonstrated significant performance improvements over the 7-week intervention and relative to the control group (P < .05). Similar gains were observed in the magnitude of adaptations in the countermovement vertical jump, 20-m sprint, Illinois change-of-direction speed, and reactive strength index for the DB-RST and TB-RST groups. Interestingly, the TB-RST group showed more gains than the DB-RST in the magnitude of adaptations in the peak and mean power outputs, as well as cardiorespiratory fitness. Moreover, the TB-RST group showed lower intersubject variability in adaptive responses across the measured performance outcomes following the training intervention. CONCLUSION: Our findings indicate that RST effectively enhances the performance of basketball players, and that implementing a TB-RST protocol is more effective than a DB-RST approach for producing greater adaptations in physiological variables-specifically anaerobic power output and cardiorespiratory fitness-over the 7-week preseason period.

Humans↗