Article

Resumo

Introdução / Objetivos

A estimulação intermitente theta-burst (iTBS), uma forma de estimulação magnética transcraniana repetitiva (rTMS), é capaz de modular a excitabilidade cortical e tem sido proposta como um método para melhorar o desempenho neuromuscular. Entretanto, ainda existem poucas evidências sobre seus efeitos agudos em exercícios de força.

Este estudo investigou os efeitos imediatos da iTBS, comparada à estimulação sham (placebo), sobre a potência anaeróbica de membros inferiores durante o Kansas Squat Test (KST) em homens treinados.

Neurol. Int. 2025, 17, x FOR PEER REVIEW of

Rafael da Silva Rego1, Vanessa Teixeira Müller1, Marco Antônio Ferreira dos Santos1, Gustavo Nascimento de Carvalho1, Rafael Pereira Azevedo Teixeira1, Diego Ignácio Valenzuela Pérez2*, Esteban Aedo-Muñoz4, Ciro José Brito5,  Bianca Miarka1*

Academic Editor: Firstname LastnameReceived: dateRevised: dateAccepted: datePublished: dateCitation: To be added by editorial staff during production.Copyright: © 2025 by the authors. Submitted for possible open access publication under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

¹Psychophysiology and Sports/Combat Performance Laboratory, Graduate Program in Physical Education, Federal University of Rio de Janeiro (BRAZIL)

Escuela de kinesiologia, Universidad Santo Tomas, Santiago (CHILE)

Universidad Metropolitana de Ciencias de la Educación (CHILE)

Physical Education Department, Federal University of Juiz de Fora (BRAZIL)

*        Correspondence: miarkasport@hotmail.com; diegovalenzuela@santotomas.cl

Background/Objectives: Intermittent theta-burst stimulation (iTBS), a form of repetitive transcranial magnetic stimulation, is capable of modulating cortical excitability and has been proposed as a method to enhance neuromuscular performance. However, evidence on its acute effects in resistance exercise tasks is limited. This study aimed to investigate the immediate effects of iTBS, compared with sham stimulation, on lower-limb anaerobic power during the Kansas Squat Test (KST) in trained men. Methods: In this randomized, double-blind, sham-controlled trial, 11 healthy resistance-trained men (age 30 ± 4.5 years; ≥2 years of training experience) were randomly allocated to iTBS (n=6) or sham (n=5). iTBS was delivered over the primary motor cortex at 100% motor threshold; sham stimulation was delivered at 20% MT. Two minutes after stimulation, participants performed the KST (15 barbell squats at 70% of one-repetition maximum) while a linear encoder measured maximum power (MAXP, primary outcome), maximum velocity (MAXV), mean propulsive velocity (MPV), and mean power (MP). Mixed-model ANOVA was used to test group × time interactions, with effect sizes (Hedges g) and 95% confidence intervals (CI) reported. Results: MAXP increased in the iTBS group compared with sham (between-group ΔΔ=+265 W; 95% CI 85 to 445; p=0.006; g=1.21). Within-group analysis showed acute increases in MAXV and MAXP after iTBS, while no significant changes were observed in sham. No adverse events were reported. Conclusions: iTBS applied over the motor cortex acutely enhanced lower-limb maximum power during the KST in trained men. These findings suggest a potential role for iTBS as a neuromodulatory strategy to transiently augment anaerobic performance, though larger and pre-registered trials are required to confirm these exploratory results.

Trial registration: 18135

Keywords: Cortical Excitability; Motor Cortex; Physical Endurance; Resistance Training; High-Intensity Exercise; Lower Extremity Strength.

1. Introduction

Transcranial stimulation techniques are characterized as non-invasive neuromodulatory methods capable of inducing, facilitating, or inhibiting the cortical excitability of specific regions of the human brain. Various stimulation techniques exist, including transcranial direct current stimulation (tDCS), applied via electrodes on the scalp, and repetitive transcranial magnetic stimulation (rTMS), which generates a magnetic pulse through a rapid variation in electrical current to stimulate the human cortex [1-3]. Due to their positive effects in treating neurological diseases and the capacity to depolarize cortical neurons, inducing action potential firing, studies over the last decades have also investigated their effects on human motor performance [4-7].

Among the application modalities of rTMS, intermittent theta-burst stimulation (iTBS), initially described by Huang et al. [8] emerges as a technique capable of modulating and inducing neural plasticity in the motor cortex within a short period (~190 seconds). iTBS consists of 3-pulse bursts at 50 Hz repeated at 5 Hz, applied for 2 seconds and separated by 10-second intervals, totaling 600 pulses over 190 seconds. Besides the brief application time, another feature of this technique is the duration of post-stimulation effects, which may last up to 60 minutes, representing an advantage compared with other neuromodulation protocols [6,7].

Regarding the effects of rTMS on physical performance, relatively few studies have been conducted. Benwell et al. [2] investigated the effects of rTMS on maximum isometric strength in a pinch test and observed a decrease in the rate of strength loss, indicating a possible attenuation of muscle fatigue. Other studies in healthy individuals using related techniques have shown improvements in muscle endurance, peak power, and reduced central fatigue [8-11]. Among these, iTBS has been highlighted as a protocol capable of inducing more robust and lasting outcomes [5,10,12,13]. Giboin et al.[5] were the first to observe the effects of iTBS on the performance of trained individuals using the Wingate test, an anaerobic power test performed on a cycle ergometer. That study showed improvements in peak power, pedal cadence, and maintenance of effort compared with placebo stimulation. These results were attributed to stimulation of the primary motor cortex (M1), with a reduction in the decline of performance caused by central nervous system (CNS) fatigue [7,14-16].

However, studies investigating iTBS in functional, sport-specific motor tasks are lacking. The free squat, a common exercise in athletic practice, can be assessed through the Kansas Squat Test (KST), a barbell squat protocol validated as a reliable method of evaluating lower-limb anaerobic power and comparable to the Wingate test [17,18]. The KST is easily implemented in athletes’ routines, using a widely practiced exercise and requiring only a free bar and weights, thus offering practicality and low cost [17,18]. By monitoring the displacement velocity of external resistance, evaluators obtain key data for tracking neuromuscular fatigue [17-19]. In addition, the analysis of execution velocity has been widely applied in resistance training (RT), since changes in movement speed at maximal intent reflect neuromuscular adaptations to training load or residual fatigue accumulation [19]. Therefore, the aim of this study is to compare the effects of iTBS and Sham (placebo) on lower limb anaerobic power in healthy individuals.

2. Materials and Methods

2.1 Study design

This study employed an experimental, randomized, double-blind, parallel-group design. Participants were evaluated before and after a single session of iTBS or sham stimulation during the KST. The random sequence was computer-generated by an investigator not involved in testing, and group allocation was concealed in sealed opaque envelopes. Participants, KST assessors, and data analysts were blinded to group assignments.

The study was conducted over four phases, with a minimum of 48 hours between sessions (Figure 1).

Note. Free and Informed Consent Form; 1RM =One-Repetition Maximum; iTBS = Theta Burst Stimulation; KST = Kansas Squat Test.

Figure 1. Experimental design and timeline of study procedures across four phases.

The study was conducted over four phases, with a minimum of 48 hours between sessions (Figure 1). On day one, participants signed the Free and Informed Consent Form (FICF), completed anamnesis, and underwent anthropometric assessment and familiarization with testing procedures. On day two, participants performed the one-repetition maximum (1RM) free barbell squat test, from which 70% of 1RM was calculated to define the load for subsequent KST assessments. On day three, participants completed the baseline KST (15 maximal-intent squats at 70% 1RM), during which velocity and power were measured with a linear encoder [4]. On day four, participants were randomly allocated to the iTBS group (100% motor threshold) or sham group (20% motor threshold). Stimulation was administered over the primary motor cortex using a standard iTBS protocol, followed by the KST retest after a two-minute interval.

The primary outcomes were maximum velocity (MAXV) and maximum power (MAXP). Secondary outcomes included mean velocity (MV), mean propulsive velocity (MPV), and mean power (MP). The trial was approved by the Ethics Committee of Local university, protocol number 66484322.9.0000.5257, and registered at [Registry, 18135/ReBEC].

2.2 Participants

A total of 11 healthy, resistance-trained men residing in Rio de Janeiro were enrolled in this study. The mean age of the sample was 30.0 ± 4.5 years, with an average height of 1.78 ± 0.06 m and body mass of 87.16 ± 10.75 kg. All participants had a minimum of two years of structured resistance training experience and reported training at least three times per week in the three months preceding data collection.

Eligibility criteria required participants to be free of musculoskeletal injuries (bone, muscle, or ligament) in the 12 months prior to enrollment, as well as free from chronic diseases, including hypertension, diabetes, cardiovascular or respiratory conditions, and mental or neurological disorders. Exclusion criteria were defined as current smoking, consumption of alcoholic beverages more than twice per week, or the use of any type of ergogenic aid, such as anabolic steroids or dietary supplements, in the month prior to participation. All athletes provided written informed consent before the study, which was presented and approved by the Ethics Committee of the local university.

Recruitment took place in Rio de Janeiro through local sports and fitness facilities, word of mouth, and laboratory announcements. A total of 200 individuals were screened for eligibility. Of these, 189 were excluded for not meeting inclusion criteria or declining participation, and 11 participants were ultimately randomized. Randomization was performed using a computer-generated sequence by an independent researcher not involved in data collection or analysis.

At baseline, the two randomized groups (iTBS and sham) were comparable in terms of age, height, and body mass, with no clinically relevant differences between them. This homogeneity strengthens the internal validity of the trial by minimizing the risk of confounding related to participant characteristics. Both participants and outcome assessors were blinded to group allocation. The sham condition reproduced auditory and sensory stimulation without inducing cortical excitability.

Although this study employed a randomized, double-blind, sham-controlled design, it was conducted as an experimental laboratory-based investigation focusing on acute neuromuscular responses rather than a clinical trial involving therapeutic intervention.

2.3 Measures

Anthropometric assessments: Body mass was measured using a calibrated digital scale (Tanita TBF-521, USA). Skinfold thickness and body fat percentage were assessed according to the Jackson and Pollock [19] seven-site protocol (subscapular, triceps, chest, suprailiac, abdominal, thigh, and subaxillary) using a skinfold caliper (Cescorf, Brazil). A single trained evaluator performed all measurements, with each site assessed three times in a non-sequential order to enhance reliability. Stature and circumferences (chest, abdomen, waist, hips, arms, forearms, thighs, and legs) were measured using an anthropometric tape (Holtain, UK). The use of one evaluator minimized inter-rater variability, and all instruments were calibrated before testing.

Kansas Squat Test: Lower-limb anaerobic power was assessed using the KST protocol [17,18]. Participants performed 15 maximal-intent squat repetitions at 70% 1RM. The primary outcome was MAXP, while secondary outcomes included MAXV, MPV, and MP.

Acquisition of velocity and power data: Velocity and power were measured with the Ergonauta I linear transducer (Florianópolis, SC, Brazil, 2021). The device records barbell displacement through an incremental rotary encoder connected by a retractable cable fixed 60 cm from the bar midpoint. Technical specifications include a resolution of 400 pulses per revolution (<1 mm per pulse) and a maximum frequency of 20 kHz [4]. Data was collected via a microcontrolled system with 1 μs time resolution and transmitted in real time to a Motorola G9 Plus smartphone (Android 11) via Bluetooth. This system has been previously validated for monitoring resistance exercise performance [18,19].

Neuromodulation iTBS: Intermittent theta-burst stimulation was applied according to the protocol of Huang et al. [8], as later used by Giboin et al. [5]. Stimulation was delivered over the primary motor cortex at 100% of the resting motor threshold in the intervention group, and at 20% in the sham group. Motor threshold was determined following IFCN guidelines, and stimulation was administered using a Magstim device with a figure-of-eight coil [20, 21].

One-repetition maximum test: The 1RM free barbell squat was determined following the protocol described by Haff et al. [6]. Testing was performed in a controlled environment (temperature 22–26°C, humidity 40–60%). Participants required between five and eight attempts to establish 1RM [22,23]. The load corresponding to 70% of 1RM was used for subsequent KST assessments.

Post-intervention testing: Two minutes after stimulation, participants performed the KST retest following the standardized warm-up and execution protocol described by Luebbers and Fry [17,18]. Execution depth was standardized by adjusting a wooden box to ensure knee flexion corresponded to the upper border of the patella. Verbal encouragement and timing control were provided by a single researcher to ensure consistency across sessions.

2.4 Intervention and Retest

iTBS and group allocation: Participants were randomly assigned to the iTBS or sham group after baseline testing. All iTBS sessions were conducted 48–72 hours after pre-intervention assessments in a controlled laboratory environment. Procedures were overseen by trained researchers experienced in the safe application of transcranial magnetic stimulation. Environmental conditions were regulated, with room temperature maintained at 22–26°C and humidity at 40–60%.

Prior to stimulation, participants were instructed to avoid strenuous physical activity, alcohol intake, or sleep deprivation in the 24 hours before testing. On the day of stimulation, they were also asked to refrain from caffeine, energy drinks, or other stimulants.

Localization and stimulation protocol: The target stimulation site was identified according to the 10–20 EEG system Jasper [9], corresponding to the primary motor cortex (M1) region. Measurements were taken to locate the stimulation area, and markings were applied using tape and a dermographic pen to ensure consistency [9,26]. iTBS was delivered with a Neuro-MS/D stimulator (Neurosoft, Anvisa: 80969860026) and a figure-of-eight coil (AFEC-02-100-C, Neurosoft). The stimulation followed the standard protocol described by Huang et al. [8] and later Giboin et al. [5], consisting of bursts of three pulses at 50 Hz repeated at 5 Hz, applied in 2-second trains separated by 10-second intervals, for a total of 190 seconds (600 pulses). The stimulation intensity in the intervention group was set at 100% of the resting motor threshold (MT), determined according to the International Federation of Clinical Neurophysiology (IFCN) guidelines.

Using the IFCN guidelines, the motor “hotspot” was identified as the scalp position that consistently produced the largest and most reliable motor-evoked potentials (MEPs) in the target muscle, with the coil held tangentially to the scalp and oriented at ~45° to the midline. The resting motor threshold (RMT) was defined as the lowest stimulation intensity that elicited MEPs of at least 50 μV in five out of ten consecutive trials in a relaxed muscle. All stimulation parameters, coil positioning, and threshold values were documented to ensure methodological reproducibility and participant safety.

Sham condition: Participants in the sham group underwent the same procedures, with coil placement and sound identical to the intervention group. However, stimulation was delivered at 20% MT, producing audible clicks and scalp sensations without inducing cortical plasticity. This procedure was used to enhance participant blinding.

Retest (post-intervention KST): After stimulation, participants returned to the testing laboratory to complete the KST. Prior to the retest, they performed a standardized warm-up: one set of five repetitions at 30% 1RM and two sets of five repetitions at 50% 1RM, as recommended by Luebbers & Fry [17,18]. The proximity of laboratories ensured that no more than two minutes elapsed between the end of stimulation and the onset of the KST.

Blinding and separation of teams: To maintain the double-blind design, researchers responsible for randomization, stimulation, and KST assessments worked independently and did not exchange information until all data collection was completed.

        2.5 Statistical Analysis

Descriptive statistics are presented as mean (M) and standard deviation (SD). Data distribution was examined using the Shapiro–Wilk test, and homogeneity of variances was checked with Levene’s test. To assess the effects of the intervention, we conducted a two-way mixed ANOVA with one between-subject factor (group: iTBS vs sham) and one within-subject factor (time: pre vs post). Group × time interaction effects were considered the primary test of interest. When significant effects were observed, Bonferroni-adjusted post hoc comparisons were performed.

The threshold for statistical significance was set at p ≤ 0.05 (two-tailed). Effect sizes (partial η² [Pη²]) for ANOVA, and Hedges’ g (g) for pairwise comparisons) with 95% confidence intervals were calculated to aid interpretation. Effect sizes were interpreted as small (η²p < 0.06), moderate (0.06–0.14), and large (>0.14). All analyses were performed using IBM SPSS Statistics, version 23.0 (IBM Corp., Armonk, NY, USA).

3. Results

A significant time × group interaction was observed for MAXV and MAXP, indicating a differential effect of iTBS compared to sham. Descriptive characteristics of participants are presented in Table 1. No meaningful differences were observed between the sham and iTBS groups at baseline in age, height, body mass, body fat percentage, 1RM squat, or relative strength index.

Table 1. Baseline characteristics of the sham and iTBS groups.

Group	Variable	M		SD (±)
Sham	Age	29.6		5.9
	Height (m)	1.78		0.07
	Body mass (kg)	85.2		5.4
	% fat	14.7		5.0
	1RM squat (kg)	130.8		14.6
	1RM Index	1.54		0.2
iTBS	Age	30.83		3.82
	Height (m)	1.79		0.06
	Body mass (kg)	88.8		14.2
	% fat	14.32		3.61
	1RM squat (kg)	130.67		18.2
	1RM Index	1.50		0.3

Note. Variables are presented as mean and standard deviation; 1RM = One repetition maximum; 1RM Index = Maximum relative strength index.

No meaningful differences were observed between the sham and iTBS groups at baseline in age, height, body mass, body fat percentage, 1RM squat, or relative strength index (Table 1).

Pre- and post-intervention Kansas Squat Test outcomes are presented in Table 2.

Table 2. Results for motor threshold, average speed, maximum speed, average propulsive speed, average power, maximum power.

Group	Variable	Pre-intervention				Post-intervention
										Sham		M	SD	Min	Max	M	SD	Min	Max
MV (m/s)	0.65	0.03	0.60	0.69	0.63	0.02	0.59	0.66
MAXV (m/s)	1.55	0.03	1.49	1.58	1.53	0.07	1.30	1.61
MPV (m/s)	0.64	0.03	0.59	0.68	0.63	0.02	0.59	0.66
MP (W)	2456.1	53.7	2345.6	2519.4	2426.9	156.0	1956.6	2595.6
MAXP (W)	2710	346	2460	3304	2709	308	2464	3246
iTBS		M	SD	Min	Max	M	SD	Min	Max
	MV (m/s)	0.56	0.03	0.52	0.63	0.61	0.02	0.6	0.7
	MAXV (m/s)	1.31	0.092*	1.09	1.4	1.46	0.04#	1.4	1.5
	MPV (m/s)	0.56	0.03	0.52	0.61	0.61	0.02	0.6	0.7
	MP (W)	2026.5	82.8	1878	2165	2253.7	83.4#	2132	2388.7
	MAXP (W)	2264.5	162.9*	2057	2461	2517	293#	1968	2809

Note. M = mean; SD = standard deviation; Min = minimum; MAX = maximum values; MT = motor threshold; MV = mean velocity, MAXV = maximum velocity, MPV = mean propulsive velocity; MP = mean power, MAXP = maximum power; *= significant difference compared with sham group; # = significant difference compared with pre-intervention, considering p≤0.05.

In the sham group, no significant differences were observed between pre- and post-stimulation conditions for MV (p = 0.509), MAXV (p = 0.773), MPV (p = 0.687), MP (p = 0.715), or MAXP (p = 0.981).

In the iTBS group, stimulation produced significant improvements in performance outcomes. Group × time interaction effects were observed for MAXV (F(1,9) = 6.10, p = 0.036, Pη² = 0.40, 95% CI [0.02, 0.62]) and MAXP (F(1,9) = 4.97, p = 0.050, Pη² = 0.36, 95% CI [0.01, 0.59]), both indicating moderate-to-large effect sizes. Within-group comparisons confirmed significant increases in MAXV (p = 0.037, g = 1.12, 95% CI [0.12, 2.07]), while MP (p = 0.060, g = 0.75, 95% CI [–0.12, 1.64]) and MAXP (p = 0.070, g = 0.88, 95% CI [–0.05, 1.78]) showed trends toward improvement. No significant differences were found for MV (p = 0.209) or MPV (p = 0.164).

When comparing change scores (Δpost–pre) between groups, no significant differences were observed for MV (p = 0.151) or MPV (p = 0.149).

4. Discussion

In the present study, the application of iTBS demonstrated an acute enhancement of neuromuscular performance, as evidenced by improvements in MAXV and MAXP during the KST. These findings may be explained by increased corticospinal excitability and enhanced motor unit recruitment, potentially mediated by short-term synaptic plasticity mechanisms within M1. From a practical perspective, iTBS may be used as a neuromodulatory priming strategy prior to explosive resistance training sessions. These results add to a growing body of research suggesting that targeted neuromodulation can influence performance variables by modulating cortical excitability and plasticity [14,24,25]. The observed improvements highlight the role of the motor cortex in coordinating complex [26,27], explosive movements and provide evidence that iTBS can acutely prime neuromuscular output.

The significant improvements observed in the iTBS group stimulated at 100% of MT align with the findings of Giboin et al. [5], who reported enhanced peak power and pedal cadence in a Wingate test following iTBS. This parallel reinforces the importance of stimulation intensity, as ergogenic effects appear to be more robust when delivered at or near the individual’s MT. Our study extends these findings by examining the effects of iTBS on free-weight squats, that is a movement requiring multi-joint coordination, large muscle mass recruitment, and integration of neural and mechanical factors. Unlike cycle ergometers or isometric tasks, free squats represent a functional, sport-relevant exercise, underscoring the ecological validity of iTBS for athletic performance.

The theoretical basis for these findings could be associated with the neurophysiological effects of rTMS on the motor cortex. iTBS is thought to induce long-term potentiation (LTP)-like effects by mimicking endogenous theta rhythms, leading to increased synaptic efficacy [5,27–29]. Studies show that iTBS reduces intracortical inhibition (likely through GABAergic pathways) while enhancing excitatory glutamatergic transmission, thereby improving the efficiency of corticospinal drive [28–30]. These changes may enhance motor unit recruitment and synchronization, reducing central fatigue and enabling greater force output. The increases in MAXV and MAXP observed in our study are consistent with these mechanisms, reflecting enhanced neural efficiency rather than changes in muscular capacity per se.

Our results complement prior evidence on the performance effects of non-invasive brain stimulation. Benwell et al. [2] reported attenuation of fatigue-related strength decline following rTMS, while other studies have observed improvements in endurance and central fatigue resistance [8–11]. In contrast, our findings emphasize explosive performance variables (velocity and power), showing that iTBS can influence not only fatigue-related endurance but also maximal neuromuscular output. Importantly, whereas most previous protocols involved isolated or ergometer-based tasks, the present study used a multi-joint free squat exercise, extending the relevance of iTBS to sport-specific performance contexts.

From a practical standpoint, these findings have implications for both sports and rehabilitation. For athletes, iTBS could serve as a preparatory priming tool to acutely boost velocity and power output before training sessions or competition, similar to strategies such as post-activation potentiation (PAP). Unlike traditional PAP, which requires heavy loading, iTBS provides a neural stimulus without additional mechanical stress, potentially reducing fatigue. In rehabilitation, iTBS could be particularly valuable for individuals recovering from neuromuscular injuries, as it may enhance strength and power without exposing tissues to high loads, thereby minimizing the risk of re-injury. This is in line with emerging evidence supporting rTMS as a facilitator of functional recovery in neurological and orthopedic populations [5, 27–30].

Despite these promising results, limitations must be acknowledged. The absence of neurophysiological measurements (e.g., EMG or corticospinal excitability) limits mechanistic interpretation. The sample size was small, which increases the risk of type II error and limits the generalizability of findings. While improvements in MAXV reached significance, changes in MP and MAXP were only trends (p ≈ 0.06–0.07), suggesting that larger studies are needed to confirm these effects. The homogeneous sample, resistance-trained men, also restricts applicability to broader populations, including women, novice trainees, and athletes from varied disciplines. Additionally, the study assessed only acute responses; whether repeated iTBS sessions could enhance long-term adaptations in strength and power remains unknown.

Future studies should therefore aim to recruit larger, more diverse samples and incorporate longitudinal designs to determine whether the acute benefits of iTBS translate into chronic training adaptations. Mechanistic measures such as motor-evoked potentials or electroneuromyography could further clarify how cortical excitability changes relate to neuromuscular outcomes. Finally, attention should be given to inter-individual variability, as not all participants may respond equally to iTBS, identifying predictors of responsiveness (e.g., baseline cortical excitability) could optimize its application.

5. Conclusions

This study demonstrated that iTBS applied over the motor cortex can acutely enhance lower-limb neuromuscular performance, particularly maximum velocity and maximum power, in resistance-trained individuals. These variables are critical in most sports, where explosive strength and speed often determine competitive outcomes. Given its non-invasive nature, brief application time, and relative ease of use, iTBS emerges as a promising adjunct to traditional training strategies within multidisciplinary performance programs.

Beyond athletic performance, iTBS also shows potential in rehabilitation contexts. Its ability to improve neuromuscular output without imposing excessive mechanical load makes it especially suitable for athletes recovering from injuries or individuals with neuromuscular impairments, where conventional high-intensity training may be limited. By facilitating gains in power and speed through neural modulation, iTBS may support both return-to-play protocols and broader therapeutic applications.

Taken together, these findings highlight iTBS as a novel and versatile tool with implications for sports performance and clinical practice. Future research with larger, more diverse samples and longitudinal designs is needed to confirm these effects and establish optimal stimulation parameters for both training and rehabilitation settings.

Author Contributions: For research articles with several authors, a short paragraph specifying their individual contributions must be provided. The following statements should be used “Conceptualization, R.S.R., V.T.M. and B.M.; methodology, R.S.R., M.A.F.S., V.T.M. and B.M.; validation, V.T.M., G.N.C. and R.P.A.T.; formal analysis, D.I.V.P., E.A.M. and C.J.B.; investigation, R.S.R. and B.M.; resources, D.I.V.P., E.A.M. and C.J.B.; data curation, M.A.F.S.; writing—original draft preparation, R.S.R. and B.M.; writing—review and editing, B.M. and R.P.A.T.; supervision, B;M; project administration, R.S.R., V.T.M. and B.M; funding acquisition, D.I.V.P., E.A.M. and C.J.B. All authors have read and agreed to the published version of the manuscript.”

Funding: Please add: “This research received no external funding”.

Institutional Review Board Statement: This study was conducted in accordance with and approved by the Ethics Committee of the Clementino Fraga Filho University Hospital (HUCFF) under 66484322.9.0000.5257.

Informed Consent Statement: All participants provided written informed consent prior to enrollment in the study, including consent for the publication of anonymized data.

Data Availability Statement: The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Acknowledgments: We thank all of the participants and the VTM Neurodiagnóstico Clinic for their dedication and commitment.

Conflicts of Interest: The authors declare no conflicts of interest.

Abbreviations

The following abbreviations are used in this manuscript:

1RM – One-repetition maximum

ANOVA – Analysis of variance

CNS – Central nervous system

EEG – Electroencephalography

ENMG – Electroneuromyography

FDI – First dorsal interosseous (muscle)

iTBS – Intermittent theta-burst stimulation

KST – Kansas Squat Test

LTP – Long-term potentiation

MAXP – Maximum power

MAXV – Maximum velocity

MEP – Motor-evoked potential

MP – Mean power

MPV – Mean propulsive velocity

MT – Motor threshold

MV – Mean velocity

rTMS – Repetitive transcranial magnetic stimulation

SD – Standard deviation

SPSS – Statistical Package for the Social Sciences

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