The research team, led by Erfan Berjisian of Edith Cowan University and colleagues from institutions in Australia, the United Arab Emirates and beyond, followed Joanna Briggs Institute guidelines and searched eight databases, including Web of Science, Scopus, SPORTDiscus, CINAHL, the Cochrane Library, Embase, MEDLINE and PubMed. Methodological quality was appraised with the AMSTAR 2 checklist, and the certainty of evidence was graded using the GRADE framework. The review was prospectively registered with PROSPERO, and the authors calculated the degree of overlap between the included reviews using the corrected covered area formula, which came out at 10.4 percent, indicating moderate overlap overall, although the reviews examining strength and hypertrophy adaptations shared a striking 64 percent of their primary studies.

The headline finding is that cold-water immersion is neither a universal elixir nor a useless fad; its effects are sharply dependent on the outcome being measured and the timing of the next performance demand. For muscular strength recovery, the evidence was consistently underwhelming. Across four meta-analyses, immersion produced no significant improvement in maximal strength compared with passive rest or alternative recovery modalities at any timepoint up to 168 hours after exercise, with standardised mean differences hovering near zero. Athletes hoping that a cold plunge will restore their deadlift or squat strength faster appear to be hoping in vain.

By contrast, explosive and power-based performance told a far more interesting, time-dependent story. Jump performance was actually impaired in the first hours after immersion, with one meta-analysis reporting a large and significant drop in jump height of 2.71 centimetres when tested immediately after cooling, a finding consistent with well-established physics: colder muscle contracts more slowly and produces less power. But the picture reversed dramatically with time. The same review found a large improvement of 4.77 centimetres at 24 hours, and other analyses confirmed small-to-large gains in jump performance between 24 and 96 hours. Muscular power followed a similar pattern, improving significantly at 24 to 72 hours after both eccentric and high-intensity exercise, with pooled effect sizes reaching 0.65 in some analyses.

Endurance performance showed yet another temporal signature. A meta-analysis of fourteen studies found a significant improvement in endurance performance when testing occurred within roughly one hour of immersion, with a standardised mean difference of 0.50, but the benefit vanished at six, 24 and 48 hours. This pattern makes physiological sense: cold-water immersion rapidly lowers tissue temperature and cardiovascular strain, which is precisely what a fatigued athlete needs before a second bout in hot conditions or during tournament play with matches on consecutive days. Beyond that acute window, however, the review found no support for cold-water immersion as a strategy to blunt cumulative endurance fatigue across multiple days of training or competition.

Perhaps the most consequential finding concerns chronic adaptation. When cold-water immersion was applied repeatedly after resistance training over several weeks, it attenuated gains in one-repetition maximum, maximal isometric strength, strength endurance and ballistic performance, with effect sizes ranging from negative 0.50 to negative 0.73 in one meta-analysis. A Bayesian meta-analysis concluded that regular post-exercise immersion likely reduces resistance training-induced hypertrophy, albeit modestly, with a corrected standardised mean difference of negative 0.22. Intriguingly, the mode of immersion mattered: subgroup analyses showed that immersing only the exercised limbs significantly blunted strength gains, whereas whole-body immersion showed no meaningful detrimental effect compared with control. Endurance adaptations, meanwhile, appeared largely unaffected, with trivial pooled effects on time-trial performance and maximal aerobic power.

The mechanistic explanation for these blunted gains lies in molecular biology rather than in the tub itself. Experimental work has shown that cold-water immersion after resistance exercise dampens anabolic signalling, reduces ribosome biogenesis and satellite cell activity, and directly impairs muscle protein synthesis rates. Cooling, in effect, suppresses the very inflammatory and signalling processes that drive muscle to grow stronger and larger after heavy training. For athletes in a strength- or hypertrophy-focused training block, the practical implication is stark: the ice bath should be kept well away from the key lifting sessions, even if it is deployed strategically after technical or aerobic work elsewhere in the week.

Not every effect was negative or neutral. Cold-water immersion consistently reduced muscle soreness from one hour up to 96 hours after exercise, with small-to-moderate effects that were largest following high-intensity exercise. It also lowered circulating creatine kinase, a marker of muscle damage, significantly between 24 and 72 hours post-exercise, with pooled effects reaching negative 1.30, although no effect was seen in the first six hours or at 96 hours. Inflammatory markers told a different story: C-reactive protein and interleukin-6 were essentially unchanged up to 72 hours, suggesting that the soreness and damage-marker benefits do not require broad suppression of systemic inflammation. On the autonomic front, a single meta-analysis of fifteen studies reported a moderate-to-large improvement in vagally mediated heart rate variability, indicating faster parasympathetic reactivation, with colder water around 9 to 15 degrees Celsius outperforming thermoneutral immersion at 28 to 35 degrees.

The review also offered practical dosing guidance. Immersions of 10 to 15 minutes at water temperatures of 10 to 15 degrees Celsius appeared most effective for reducing muscle soreness, while 10 to 15 minutes at 5 to 10 degrees Celsius had the highest probability of being optimal for lowering creatine kinase and improving jump performance at 24 to 48 hours. Intermittent and continuous protocols performed similarly, and longer immersions of 16 to 20 minutes were not consistently beneficial, with experimental work cautioning that prolonged or aggressive cooling may impair glycogen restoration and delay recovery from muscle damage.

The authors are candid about the limitations of the evidence base. All fifteen included reviews were rated as low or critically low methodological quality, and most outcomes carried low to very low certainty of evidence, driven mainly by inconsistency, imprecision and the near-impossibility of blinding participants to frigid water. Roughly 90 percent of participants were male, leaving sex-specific responses to cold exposure largely unexplored. Still, the overarching message is clear and actionable: cold-water immersion should be periodised and individualised rather than applied routinely after every session. It is most defensible when recovery time is short, thermal strain is high, and the next bout is imminent, and it should be avoided immediately before explosive performance and during phases where strength and muscle growth are the priority. The ice bath, it turns out, is a precision tool, not a daily ritual.

Subject of Research: Effects of post-exercise cold-water immersion on athletic performance recovery and training adaptation

Article Title: Strategic Application of Post-exercise Cold-Water Immersion to Enhance Performance Recovery and Adaptation: An Umbrella Review of 15 Published Systematic Reviews with Meta-analysis

Article References: Berjisian, E., Miraftabi, H., Ihsan, M., Homer, K. A., Kendall, K., Roberts, L., & Abbiss, C. (2026). Strategic Application of Post-exercise Cold-Water Immersion to Enhance Performance Recovery and Adaptation: An Umbrella Review of 15 Published Systematic Reviews with Meta-analysis. Sports Medicine – Open, 12(1), Article 145. https://doi.org/10.1186/s40798-026-01116-8

Image Credits: AI Generated

DOI: 10.1186/s40798-026-01116-8

Keywords: cold-water immersion, exercise recovery, athletic performance, muscle soreness, creatine kinase, strength training, hypertrophy, endurance performance, heart rate variability, meta-analysis, sports medicine, recovery protocols

The research team, based at the Federal University of Rio de Janeiro, recruited eleven healthy young adults with an average age of 29, all of whom had been training with weights for at least a year and screened positive for subclinical generalized anxiety disorder using validated questionnaires. To qualify, participants needed scores of at least 6 on the generalized anxiety subscale of the Psychiatric Diagnostic Screening Questionnaire and 45 or above on the Penn State Worry Questionnaire, thresholds previously validated for identifying heightened, clinically relevant worry that falls short of a formal diagnosis.

The experimental design was a rigorous randomized crossover: each participant completed both resistance training protocols on separate laboratory visits separated by at least 72 hours, with order determined by balanced randomization. The two sessions were engineered to match volume load and relative intensity while differing sharply in structure. The first protocol, 3 x 10 with 60-second rest intervals, involved three sets of ten repetitions at 85 percent of the participant’s ten-repetition maximum, performed on leg press and leg extension machines. The second, 8 x 3 with 120-second rest intervals, spread eight sets of three repetitions at 85 percent of the three-repetition maximum across the same exercises. Both protocols sat firmly in the high-intensity zone, but the shorter-rest configuration imposes far greater cardiometabolic strain, driving up heart rate, blood lactate, and the acute sensations of distress that exercise psychologists call interoceptive signals.

Anxiety, measured with the State subscale of the State-Trait Anxiety Inventory, dropped significantly 30 minutes after both sessions. After the traditional 3 x 10 protocol, state anxiety fell from a baseline of 44.1 to 40.3 points, a large effect size of 1.1. After the cluster-style 8 x 3 protocol, it fell from 44.8 to 41.9, a moderate effect of 0.65. Crucially, the difference between protocols was not statistically significant, meaning that the anxiolytic effect did not depend on which configuration the participants performed. Total mood disturbance, a composite score from the Profile of Mood States that weighs tension, depression, anger, fatigue, and confusion against vigor, declined after both sessions as well, with effect sizes exceeding 1.3 in each case.

Beneath those headline results, the two workouts told very different emotional stories. Only the traditional high-repetition protocol significantly reduced anger, while only the cluster protocol cut fatigue and boosted vigor. More telling were the measures taken during exercise itself. Using the Feeling Scale, an 11-point scale from very bad to very good, the researchers tracked affective valence set by set. The 3 x 10 session pushed participants steadily into the high-activation displeasure quadrant of the circumplex model of affect, the emotional territory of tension and distress, and produced significantly lower post-exercise pleasure than the cluster session. The 8 x 3 session, by contrast, shifted participants toward high-activation pleasure, the quadrant associated with energy and vigor.

The perceptual side of the story was equally lopsided. Participants rated their exertion significantly higher after the 3 x 10 protocol, 9.6 versus 8.1 on a repetitions-in-reserve-based scale, and enjoyed it significantly less, scoring 42.3 versus 46.1 on the eight-item Physical Activity Enjoyment Scale. In other words, the two sessions moved roughly the same amount of iron but felt like entirely different experiences, one punishing and unpleasant, the other demanding yet enjoyable and energizing.

Those differences mattered for the psychological outcomes. In the traditional protocol, the magnitude of improvement in total mood disturbance correlated strongly with exercise enjoyment (r = 0.872) and negatively with post-exercise affective valence (r = -0.809), while changes in state anxiety tracked changes in affective valence (r = 0.547). In the cluster session, enjoyment correlated strongly with reductions in anger (r = 0.921), confusion (r = 0.823), and total mood disturbance (r = 0.821). These associations, though drawn from a small sample and not proof of causation, support the theoretical framework the authors set out to test: contemporary dual-mode theory holds that how exercise feels, the dynamic interplay between cognitive appraisal and bodily signals such as muscular burn and cardiovascular strain, shapes emotional outcomes, and hedonic theory predicts that people return to activities that feel good and avoid those that do not.

The findings complicate decades of dose-response research. Earlier studies, including work by O’Connor and colleagues in 1993 and Bartholomew and Linder in 1998, suggested a Goldilocks zone: moderate-intensity lifting reduced anxiety while low and high intensities did not, and one 2005 study found that lifting at 100 percent of the ten-repetition maximum actually increased anxiety. The new results show that high-intensity resistance exercise at 85 percent of maximal load, in two different configurations, reliably lowers anxiety in an anxious population when volume load is comparable. The authors suggest one intriguing explanation: exposure to controlled, manageable physiological stress may itself train emotion regulation, enhancing perceived control and cognitive reappraisal, effects that may be especially pronounced in people with elevated baseline anxiety.

Why did the more grueling session still calm the participants even while feeling worse? The researchers argue that anxiolysis and affective experience are partly separable pathways. The acute reduction in state anxiety may follow from physiological and psychological stress-processing mechanisms common to both protocols, while the subjective experience, pleasure, effort, and enjoyment, shapes which dimensions of mood improve and whether people will come back for more. That distinction has practical weight: if a workout leaves an anxious person feeling drained and miserable, adherence will likely suffer, and the long-term benefits of training will never materialize. The cluster configuration, with its long rests and brief sets, offered the same anxiety relief with less fatigue, more vigor, and greater enjoyment, making it the more attractive prescription for people who dread the gym.

The authors are candid about the study’s limits. The sample was small, only six participants completed the full mood-state analyses, and the study relied on self-report measures vulnerable to response bias. Only three women participated, precluding any analysis of sex differences, and the absence of a non-exercise control condition means expectancy effects or natural mood fluctuations cannot be fully ruled out, though the crossover design controls for many individual factors. Still, the moderate-to-large effect sizes observed suggest real clinical relevance, and the researchers call for larger trials with control conditions and long-term follow-up to test whether the perceptual and affective mechanisms identified here mediate the chronic mental health benefits of resistance training.

Even with those caveats, the study lands at a moment when the mental health case for strength training is accelerating. Meta-analyses have already established that resistance exercise training reduces anxiety symptoms in randomized controlled trials, and the mechanisms proposed for its effects span endorphin release, cortisol regulation, monoaminergic modulation, and improved sleep. What this new work adds is a sharper picture of the psychology inside the workout: anxiety relief appears robust across training configurations, but the feeling of the session, effort, pleasure, and enjoyment, is not a luxury. It may be the very pathway through which lifting weights rewires an anxious mind, and the detail most likely to determine whether an anxious young adult ever picks up a barbell twice.

Subject of Research: Acute effects of different resistance training configurations on anxiety and mood in young adults with subclinical generalized anxiety disorder

Article Title: Resistance Training Performed in Different Configurations Reduces Anxiety and Improves Mood States in Young Adults with Subclinical Generalized Anxiety Disorder

Article References: de Oliveira, L. C., Gobbo, H. R., Barbosa, G. M., Semmer, L. V., & de Oliveira, G. V. (2026). Resistance Training Performed in Different Configurations Reduces Anxiety and Improves Mood States in Young Adults with Subclinical Generalized Anxiety Disorder. Trends in Psychology. https://doi.org/10.1007/s43076-026-00523-w

Image Credits: AI Generated

DOI: 10.1007/s43076-026-00523-w

Keywords: resistance training, anxiety, generalized anxiety disorder, mood states, affective valence, exercise psychology, state anxiety, perceived exertion, exercise enjoyment, mental health, randomized crossover trial, strength training

The research team, led by Tsuyoshi Nagatani of Edith Cowan University alongside colleagues including Christopher Latella, Paul Comfort, Eric Drinkwater and G. Gregory Haff, compared three alternatives to the traditional set, in which repetitions are performed consecutively with rest only between sets. Cluster sets insert brief rest periods between individual repetitions or small groups of repetitions within a set, adding total rest and lengthening the session. Rest-redistribution strategies take a different route: instead of adding rest, they rearrange the rest already in the program. Intra-set rest-redistribution carves a slice out of the between-set rest and moves it inside the set, while inter-set rest-redistribution splits a large set into many smaller ones, for example turning three sets of ten into six sets of five, keeping total rest constant.

Because only a handful of studies have directly pitted cluster sets against rest-redistribution, the authors turned to a network meta-analysis, a statistical framework that combines direct comparisons with indirect ones linked through a common comparator, in this case the traditional set. They searched PubMed and Web of Science, screened 1,121 records, and ultimately included 37 studies encompassing 611 unique participants, 557 of them male and 54 female. The outcomes of interest were mean velocity, mean propulsive velocity and peak velocity, the kinematic signatures that velocity-based training practitioners use to gauge fatigue and readiness. Analyses were run in a Bayesian framework using Markov Chain Monte Carlo simulation, with posterior standardized mean differences and 95 percent credible intervals, and treatments were ranked with SUCRA scores, which express the probability that each set structure is the most effective.

The headline finding is that all three alternative structures beat the traditional set at preserving mean velocity. Cluster sets showed a standardized mean difference of 0.60 (95 percent credible interval 0.42 to 0.80), intra-set rest-redistribution 0.41 (0.08 to 0.75) and inter-set rest-redistribution 0.42 (0.26 to 0.61). For peak velocity, cluster sets (0.48, 0.20 to 0.76) and intra-set rest-redistribution (0.39, 0.04 to 0.73) again outperformed traditional sets, but the credible interval for inter-set rest-redistribution crossed zero, leaving its effect on peak velocity uncertain. In the SUCRA rankings, cluster sets held the highest probability of being the best structure for both mean velocity (99.7 percent) and peak velocity (95.6 percent), followed by intra-set rest-redistribution and then inter-set rest-redistribution.

Yet the more consequential result is what the analysis did not find. When the alternative structures were compared directly with one another, the credible intervals for mean and peak velocity crossed zero in every case. Cluster sets versus intra-set rest-redistribution produced a credible interval of −0.19 to 0.58 for mean velocity, and cluster sets versus inter-set rest-redistribution ranged from −0.05 to 0.41. In plain terms, although cluster sets carry the highest probability of ranking first, the evidence does not support a practically meaningful advantage over either redistribution strategy. The physiological logic behind the cluster advantage is straightforward: brief intra-set pauses allow partial resynthesis of phosphocreatine, blunting the metabolic disruption, lactate accumulation and neural drive decrements that cause velocity to crater in uninterrupted sets. But rest-redistribution achieves a similar effect without adding a single second to the session, which is precisely why the question of whether cluster sets are meaningfully better matters so much to practitioners.

The authors also tested whether the benefits depend on context, using network meta-regressions. Exercise type, comparing lower-body movements such as squats and clean pulls with the bench press, did not significantly moderate the effects, with a regression coefficient of 0.10 and a credible interval spanning zero, although there was a tendency toward larger benefits in lower-body exercise, plausibly because larger muscle masses and longer ranges of motion generate greater metabolic stress. Relative training intensity, split between moderate loads of 60 to 79 percent of one-repetition maximum and high loads of 80 percent or more, likewise failed to moderate the effects (coefficient 0.15, credible interval −0.12 to 0.43). The practical implication is that alternative set structures appear robust across exercise selection and loading zones, rather than being niche tools for specific lifts or intensity zones.

Peak velocity told a more nuanced story. The uncertain effect of inter-set rest-redistribution was driven partly by the small number of studies and by the exercises examined. The one study reporting a clear peak-velocity benefit examined the clean pull from the floor, a full-range movement with large barbell displacement and high metabolic demand, whereas the two studies showing no benefit used partial weightlifting derivatives, the hang pull and countermovement shrug, which involve shorter displacement and less time under tension and may simply not generate enough fatigue for redistributed rest to matter. The authors caution that the apparent superiority of cluster sets and intra-set redistribution for peak velocity may therefore be inflated by these study characteristics, and they call for more research on full-range, multi-joint movements.

For coaches, the practical takeaway may be the most valuable part of the paper. Because intra-set rest-redistribution produced velocity outcomes statistically comparable to cluster sets without extending session duration, it emerges as a time-efficient alternative for athletes training under tight schedules. Inter-set rest-redistribution, while effective for mean velocity, carries logistical friction: some implementations redistribute rest between every single repetition, forcing athletes to rack and un-rack a barbell dozens of times, and in team environments one athlete must finish all their scattered repetitions before partners can rotate through. The authors suggest that cluster sets and intra-set redistribution are the more practical choices in real-world settings, with the final decision guided by session time, equipment and training context rather than by any large performance differential.

The review is not without limitations, which the authors acknowledge candidly. Several studies comparing intra-set rest-redistribution with traditional sets failed to equalize total rest duration, inadvertently giving the intervention more recovery and potentially inflating its benefit. Evidence for peak velocity rested on far fewer studies than mean velocity, some consistency checks could not be performed for certain comparisons, and the participant pool was overwhelmingly male, preventing any analysis of sex as a moderator. Publication bias was detected for the mean velocity model, though not for peak velocity. Registered prospectively on the Open Science Framework, the review nevertheless represents the first analysis to treat the two rest-redistribution variants as distinct constructs, and its central message is likely to reshape how velocity-focused programming is discussed: the way rest is arranged matters far more than the label attached to it, and almost any thoughtful departure from the traditional set will keep the bar moving faster.

Subject of Research: A systematic review and Bayesian network meta-analysis comparing cluster set and rest-redistribution set configurations for maintaining movement velocity during resistance training.

Article Title: The Effectiveness of Cluster vs. Rest-Redistribution Set Configurations to Maintain Movement Velocity During Resistance Training: A Systematic Review and Bayesian Network Meta-analysis

Article References: Nagatani, T., Latella, C., Yang, J., Kendall, K. L., Vial, S., Comfort, P., Drinkwater, E. J., & Haff, G. G. (2026). The Effectiveness of Cluster vs. Rest-Redistribution Set Configurations to Maintain Movement Velocity During Resistance Training: A Systematic Review and Bayesian Network Meta-analysis. Sports Medicine – Open, 12(1), Article 141. https://doi.org/10.1186/s40798-026-01106-w

Image Credits: AI Generated

DOI: 10.1186/s40798-026-01106-w

Keywords: resistance training, cluster sets, rest redistribution, movement velocity, velocity loss, neuromuscular fatigue, network meta-analysis, strength and conditioning, velocity-based training, set structure, phosphocreatine, sports science

The research team recruited twenty-two players from the Tunisian national U15 soccer program, all of whom qualified as Tier 3, or highly trained, athletes under the classification framework proposed by McKay and colleagues. The girls, aged 14.9 plus or minus 0.8 years and assessed at Tanner stage 3 of pubertal development, were randomly assigned to either a strength training group of eleven players or an active control group of eleven who continued their normal soccer schedule. Both groups trained five times per week for ninety minutes and played a competitive match each weekend, and statistical analysis confirmed that total training loads, calculated by multiplying session ratings of perceived exertion by session duration, were essentially identical between groups at roughly 1,160 arbitrary units. That equivalence matters, because any difference in outcomes could then be attributed to the strength intervention itself rather than to a simple mismatch in workload.

The strength program was deliberately periodized across three four-week cycles. In the first cycle, players performed full-body exercises such as leg press, hip thrust, squat, bench press, lat pull-down and calf raises at 40 to 60 percent of their one-repetition maximum, completing three sets of fifteen repetitions with deliberately slow movement. The second cycle escalated to three sets of twelve, ten and eight repetitions at 60 to 75 percent of one-repetition maximum, while the third cycle climbed to sets of ten, eight and six repetitions at intensities approaching 85 percent. One-repetition maximum tests were repeated before each cycle to recalibrate loads, ensuring progressive overload, and no strength work was performed during the fourth week of each cycle to allow recovery and consolidation of adaptations.

The physical results were unambiguous. After twelve weeks, the strength group posted large and statistically significant gains in maximal dynamic strength across all three tested lifts, with one-repetition maximum improvements on the bench press, lat pull-down and leg press reaching post hoc significance at p less than 0.001 and partial eta squared values of 0.41, 0.43 and 0.36 respectively, all well beyond the threshold for large effects. Body composition shifted in parallel: the strength group gained lean body mass while simultaneously reducing body fat percentage, a combination the authors attribute to stimulated muscle hypertrophy and increased energy expenditure. The control group showed no comparable changes. Because these athletes had never previously undergone systematic strength training, the researchers suggest the early gains were driven largely by neural adaptations, including improved motor unit recruitment and firing frequency, a phenomenon typically dominant during the first four to six weeks of a resistance program before hypertrophy becomes the primary mechanism.

The soccer-specific findings may be the most striking for coaches. Using the Loughborough Soccer Passing Test, a validated field assessment in which players complete sixteen timed passes against color-coded targets while penalties are added for misses, wrong targets and handling errors, the strength group improved its total score by roughly 22 percent. Crucially, the improvement came overwhelmingly from a reduction in penalties, which fell by more than 65 percent in the strength group compared with only about 11 percent in controls. The test demands simultaneous ball control, rapid decision-making and precise body positioning in a confined space, so the authors interpret the penalty reduction as evidence of better information processing and a strengthened connection between cognition and motor execution. Previous reviews have shown that various training modalities can improve passing test scores, but demonstrating this from a pure strength intervention in adolescent girls adds a genuinely novel data point.

Executive function, the suite of mental skills that governs inhibition, cognitive flexibility and attentional control, was assessed with the classic Stroop test, in which participants must name the ink color of a word when the word itself names a different color, thereby forcing the brain to suppress an automatic reading response. Across three subtasks covering word reading, color naming and the interfering word-color condition, the strength training group improved significantly, with the critical group-by-time interaction for the Stroop word-color test reaching p equal to 0.006 and a large effect size, while the control group did not improve beyond time-related practice effects. The authors caution that some portion of the gain may reflect measurement variability or learning effects, but the pattern aligns with a 2020 meta-analysis by Landrigan and colleagues showing that resistance exercise reliably lifts cognitive performance, and with neurophysiological work by Kidgell and by Hortobágyi linking strength training to enhanced corticospinal excitability and synaptic efficiency.

The study also probed the molecular machinery that is often assumed to underlie these cognitive benefits. Blood samples were drawn in a fasted state, twenty-four hours after the final training session and during the follicular phase to control for hormonal fluctuation, and analyzed for basal serum concentrations of brain-derived neurotrophic factor, or BDNF, and insulin-like growth factor 1, or IGF-1. In animal models, exercise-induced elevations of these molecules drive neurogenesis, long-term potentiation and synaptic plasticity, and several human studies have reported increased IGF-1 after resistance training. Yet here, despite clear behavioral improvements, neither marker changed significantly between or within groups. The authors suggest several explanations: athletes with already high fitness levels may maintain BDNF and IGF-1 at a physiological homeostasis that leaves little room for further elevation, participants had an average body mass index below 25, a range in which exercise typically produces no detectable BDNF change, and the effects of long-term training on circulating BDNF may be transient rather than cumulative, with acute spikes returning to baseline between sessions.

The findings carry practical weight for a sport in which cognition increasingly appears to separate elite from sub-elite performers. Soccer constantly presents players with multi-task demands, requiring them to dribble or pass while simultaneously tracking opponents, teammates and passing lanes under severe time pressure, and prior research has shown that Stroop performance can distinguish high-level from low-level players. If two supervised strength sessions per week, easily accommodated within an in-season schedule, can meaningfully sharpen inhibitory control and reduce passing errors, the cost-benefit calculation for youth academies changes considerably. The researchers explicitly recommend that coaches integrate strength training into regular programs to develop both physical fitness and cognitive function in young female athletes, noting that adherence in this trial exceeded 99 percent and that no training-related injuries occurred.

The study is not without limitations, which the authors transparently enumerate. Executive flexibility was measured with only a narrow test battery; additional neurotrophins such as NT-3 and NT-4 were not sampled; sleep, stress and fatigue were uncontrolled; and the power analysis was based on a single outcome despite multiple tested domains, leaving a residual risk of type I error. Pubertal development and menstrual cycle phase may also have introduced variability despite careful scheduling of blood draws. Still, as the first trial of its kind in young, highly trained female soccer players, the work opens a productive line of inquiry. The authors call for future studies measuring neurovascular and neuroendocrine responses during and after strength interventions, and for trials comparing strength training against dedicated cognitive training, to determine whether the mental gains observed here can be amplified, sustained and, ultimately, translated into match-day advantage on the pitch.

Subject of Research: Effects of strength training on cognitive function and neuroplasticity markers in highly trained young female soccer players.

Article Title: Effects of Strength Training on Cognitive Function, Brain-Derived Neurotrophic Factor and Insulin-Like Growth Factor 1 in Highly-Trained Young Female Soccer Players

Article References: Bousselmi, M., Zouhal, H., Darragi, M., Karamti, H. M., Ben Hmid, A., Zamali, I., Ben Ahmed, M., Krir, A., Zouita, S., Laher, I., Hackney, A. C., Granacher, U., & Ben Moussa Zouita, A. (2026). Effects of Strength Training on Cognitive Function, Brain-Derived Neurotrophic Factor and Insulin-Like Growth Factor 1 in Highly-Trained Young Female Soccer Players. Sports Medicine – Open, 12(1), Article 138. https://doi.org/10.1186/s40798-026-01103-z

Image Credits: AI Generated

DOI: 10.1186/s40798-026-01103-z

Keywords: strength training, cognitive function, female soccer, BDNF, IGF-1, Stroop test, LSPT, youth athletes, neuroplasticity, muscle strength, executive function, randomized controlled trial