Exploring the acute recovery effects of dry cupping therapy and electrical stimulation on anaerobic performance metrics in active individuals: A quasi-experimental crossover study

Abstract

Background:

This quasi-experimental crossover study aimed to examine the acute effects of dry cupping therapy (DCT) and neuromuscular electrical stimulation (NMES) on fatigue and perceived exertion in anaerobic performance among physically active individuals.

Methods:

Twelve male participants (mean age: 24.1 ± 2.37 years), all students from the Faculty of Sports Sciences, were recruited to participate voluntarily. Anaerobic performance parameters, including peak power, mean power (MP), and fatigue index (FI), were assessed using a Monark 839E cycling ergometer under 3 distinct conditions: NMES, DCT, and a control condition (no intervention), with each session separated by a 48-hour rest period. Perceived exertion was evaluated immediately following each test session using Borg’s rate of perceived exertion (RPE) scale. Both NMES and DCT were administered bilaterally to the hamstring (m. hamstring) and quadriceps femoris (m. quadriceps femoris) muscles for 20 minutes before testing.

Results:

The results revealed no statistically significant differences in peak power and MP across the conditions. However, significant effects were identified for FI (F(2, 22) = 4.08, P = .031, ηp² = 0.27) and RPE (F(2, 22] = 8.88, P = .0015, ηp² = 0.45). Post hoc pairwise comparisons indicated that NMES significantly reduced FI compared to the control condition (P = .0311), with a small to medium effect size (Cohen’s d = 0.44). In terms of RPE, DCT significantly lowered values compared to both the control (P = .0018) and NMES conditions (P = .0005), demonstrating medium (Cohen’s d = 0.74) and small to medium (Cohen’s d = 0.37) effect sizes, respectively.

Conclusions:

While NMES and DCT did not elicit acute improvements in peak or mean anaerobic power, both interventions effectively mitigated fatigue and reduced perceived exertion during maximal anaerobic exercise. These findings suggest that NMES and DCT may serve as valuable recovery modalities for mitigating fatigue in sports characterized by high anaerobic demands. Future research should investigate the chronic effects of these interventions and explore their utility among trained athletes to determine their broader applicability in enhancing athletic performance.

1. Introduction

Today, with the advancement of technology and modern approaches to training methods, significant improvements have been observed in athletes’ physical conditioning, leading to higher-intensity competitions in both team and individual sports. Activities in sports typically involve explosive movements such as forward, backward, and lateral actions, combined with varying intensity of running. In addition, activities in combat sports, such as throwing punches or kicks and evading an opponent’s moves, often involve explosive actions and sudden speed changes. Therefore, in both team and individual sports, successful performance requires the ability to execute movements at high speeds.^[1] These speed demands can lead to performance decline when complex functional systems fail to cope with the demands.^[2] In this context, the importance of anaerobic power and capacity, which refers to the body’s potential to maintain high-intensity performance over an extended period, is crucial for success in sports.^[3]

Anaerobic power and capacity are utilized based on the depletion of 2 distinct anaerobic energy systems: the adenosine triphosphate-creatine phosphate (ATP-CP) and anaerobic glycolysis systems. It is widely accepted that the ATP-CP system measures anaerobic power, while anaerobic glycolysis reflects anaerobic capacity.^[4] The ATP-CP (phosphagen or alactic anaerobic) system is the predominant energy system used in short-duration, high-intensity activities, such as sprints and resistance training, and is highly active at the onset of all exercises regardless of the intensity.^[5,6] On the other hand, anaerobic glycolysis (the lactic acid or glycolytic system) becomes the dominant energy system in activities lasting between 20 seconds and approximately 2 minutes.^[7]

It is important to distinguish the term “power,” which refers to the rate at which energy is produced, from “capacity,” which represents the total amount of energy generated.^[8] In this regard, anaerobic power and capacity are considered performance indicators in high-intensity muscular activities lasting from several seconds to a few minutes.^[9] In other words, the ability to produce maximal or peak mechanical power within a few seconds (peak power [PP] or maximal anaerobic power) and the ability to sustain high power output for a short period (mean power [MP] or maximal anaerobic capacity) are key determinants of performance.^[10] PP produced over a duration exceeding one (1) second reflects anaerobic power, whereas the amount of work performed over a duration exceeding thirty (30) seconds indicates anaerobic capacity. Thus, anaerobic power refers to the rate of maximal energy flow or maximal mechanical power generated during high-intensity exercise. In contrast, anaerobic capacity represents the total amount of high-intensity work supported by energy systems independent of oxygen.^[11]

For many years, researchers have explored various methods to enhance athletic performance.^[12] Neuromuscular electrical stimulation (NMES) is a rehabilitation technique that can be easily performed using portable devices, aimed at both muscle reeducation and facilitation, and targeting neuromuscular tissue development.^[13] This method, which has been in use for a long time and continues to retain its clinical relevance, involves delivering electrical stimuli to the motor points of muscles within the neuromuscular tissue to induce muscle contractions.^[14,15] The underlying premise of NMES is to generate more motor unit action potentials than would typically occur during maximal voluntary muscle contractions.^[16] In the literature, NMES applications have been shown to significantly improve isokinetic muscle strength in both healthy individuals^[17–19] and those recovering from anterior cruciate ligament surgery or knee arthroplasty.^[20–22] Moreover, sessions of electrotherapy applied to the quadriceps femoris (m. quadriceps femoris) and hamstring (m. hamstring) muscle groups have demonstrated increases in muscle hypertrophy, electromyography activity, and mobility levels.^[13,23,24]

Dry cupping therapy (DCT), one of the complementary and traditional treatment methods, is among the oldest therapeutic techniques.^[25] Although the use of traditional and complementary medicine declined with modern medical discoveries in the past century, its popularity has been increasing in recent times due to factors such as the rise of chronic diseases, a decrease in cure rates for certain conditions, the increase in diseases with unknown causes and treatments, a growing reluctance to use chemical medications, and the desire to return to a natural lifestyle.^[26] Cupping therapy is applied in 2 main forms: dry and wet cupping. In both methods, cups are placed on soft tissue of varying sizes, creating a negative pressure. In DCT, also known as static cupping therapy, no blood is drawn from the body. Air is removed from the cup to create a vacuum, causing the skin to rise due to the negative pressure. Wet cupping begins similarly to DCT, but small incisions are made on the treated area to allow blood to be drawn out.^[27–29] In the literature, cupping therapy is commonly studied in musculoskeletal disorders^[30] or performance parameters in athletes engaged in team sports, such as joint range of motion, jumping ability, pain, functionality, recovery, and quality of life.^[31–34]

Considering the necessity for high-speed and high-intensity exercises, such as sprints and jumps, during numerous sporting activities, it is crucial for athletes to accurately assess their anaerobic power.^[35] Anaerobic tests, which involve short-duration maximal exercise efforts, can be conducted in different ways in both field and laboratory settings, depending on the parameters being measured and the protocols used.^[1] Common examples of tests used to measure anaerobic performance include vertical jump and long jump distance, short-distance sprint times, and tests that assess maximal power during brief cycling efforts.^[11] However, the most popular test protocol used to measure anaerobic components is the Wingate Anaerobic Test (WAnT), which is considered the gold standard across many disciplines.^[36–38]

In many studies, the chronic effects of NMES application on muscle strength following specific training periods, as well as the impact of DCT on musculoskeletal disorders and certain performance parameters, have been investigated. However, to our knowledge, there is no existing research that examines the acute effects of NMES, one of the electrical stimulation methods, and DCT, a complementary and traditional treatment, on anaerobic performance. Therefore, the present study aims to explore the acute effects of NMES and DCT applications on fatigue and perceived exertion in anaerobic performance, which is measured by WAnT in physically active individuals. Based on the premise that an increase in power is critical for successful performance in athletic activities, it is hypothesized that the positive acute effects of NMES and DCT on anaerobic performance could contribute to improved anaerobic performance in athletes due to the ease of use and time efficiency of both applications. Accordingly, it is hypothesized that NMES and DCT applied to the lower body will have a positive effect on power values during a maximal cycling all-out anaerobic test.

2. Materials and methods

2.1. Participants

This study included 12 male students (age: 24.1 ± 2.37 years; height: 172.63 ± 6.43 cm; body mass: 69.09 ± 9.28 kg; body mass index: 23.12 ± 2.16 kg/m²) enrolled in the Faculty of Sports Sciences, who participated voluntarily. The minimum sample size for the present study was determined using G*Power Software (version 3.1.9.7; University of Düsseldorf, Germany). An a priori power analysis was conducted with F-tests, by the study’s repeated measures design, incorporating a within-subjects ANOVA with a within-between interaction analysis. The study design involved 3 repeated measurements from a single group across 3 points. The error probability (α) was set at 0.05, the correlation among repeated measures was assumed to be 0.5, and the non-sphericity correction was set to 1. Based on these parameters, a minimum effect size (Cohen’s f) of 0.40 was established,^[39,40] yielding an actual power of 81.62%. Participants who had not experienced any lower body muscle injuries in the past 6 months and were not taking any medications that could negatively affect the study results were included. Written and verbal information was provided to the participants regarding the study’s purpose, test procedures, data collection process, associated risks of participation, and potential benefits. The experimental protocol was approved by the Scientific Research and Publication Ethics Committee of Igdir University (SRPEC approval no. 14/7-5-2024), and all procedures were conducted following the Helsinki Declaration.

2.2. Experimental approach to the study

The study employed a quasi-experimental crossover design involving 12 participants to evaluate the effects of 3 interventions – NMES, DCT, and a control condition – on anaerobic performance outcomes. This design allowed each participant to serve as their control, facilitating direct comparison across interventions.^[41] As illustrated in Figure 1, the protocol began with a familiarization session 1 week before the measurements, during which participants were introduced to the testing procedures. Each session began with a standardized warm-up, consisting of 10 minutes of low-intensity running on a treadmill (Trackmaster TMX425CP, Newton, KA) at 40% of maximum heart rate, followed by 5 minutes of stretching exercises targeting both upper and lower body muscles. Participants performed an initial WAnT between 09:00 and 11:00 to establish baseline values without any intervention. To control circadian rhythm effects, all tests were conducted within the same time window. Following this baseline test, a 48-hour rest period was observed to allow recovery before beginning the interventions. Participants were then randomly assigned to 2 groups, with Group 1 receiving NMES and Group 2 receiving DCT in the first treatment phase. After another 48-hour rest period, a crossover occurred, with Group 1 receiving DCT and Group 2 receiving NMES. This crossover ensured that each participant experienced both treatment conditions while minimizing carryover effects. Anaerobic performance parameters, including absolute and relative PP and MP in watts and watts per kilogram and FI in percentage were measured using a cycling ergometer (Monark 839E) over 3 nonconsecutive days. Consistent with standardized testing protocols, individual settings for saddle height and upper body position were recorded and kept constant for each participant throughout all sessions to control for postural influence on performance.^[42] No verbal encouragement or motivation techniques were used, and immediately following each test, participants rated their perceived exertion using Borg’s 20-point rate of perceived exertion (RPE) scale.^[43] The crossover structure and repeated measures allowed for a balanced comparison of the interventions by minimizing inter-participant variability and enhancing the reliability of the results. The experimental design is visually depicted in Figure 1.

Figure 1.

Experimental design of the study. Schematic overview of the quasi-experimental crossover design. Participants (n = 12) underwent 3 testing sessions separated by 48-hour rest intervals, including a control (no intervention), NMES (neuromuscular electrical stimulation), and DCT (dry cupping therapy) condition, with familiarization preceding the test sequence. Each participant experienced all 3 conditions in randomized order. DCT = dry cupping therapy, NMES = neuromuscular electrical stimulation.

2.3. Protocols

2.3.1. Neuromuscular electrical stimulation (NMES) protocol

The NMES application was performed bilaterally on the motor points of the thigh’s large anterior and posterior muscle groups, specifically the m. hamstring and m. quadriceps femoris, using a muscle rehabilitation device (Cefar Compex^® Rehab, Cefar-Compex Medical Ab, Sweden) equipped with various programs tailored for rehabilitation purposes, including a denervation mode. For the placement of adhesive electrode pads, the proximal electrode for the m. quadriceps femoris muscle was positioned 15 cm lateral to the prominence of the spina iliac anterior superior, and the distal electrode was placed on the thickest point of the m. vastus medialis muscle, 4 cm proximal to the superior line of the patella. For the hamstring muscle group on the posterior thigh, adhesive electrodes were attached to the origin of the m. rectus femoris and the motor point of the m. semitendinosus (Fig. 2). Since everyone’s electrical excitability varies, the current was gradually increased while observing the participant until a tetanic contraction was achieved. In cases where muscle contractions diminished during the NMES application, feedback was obtained from the participants, and the current was increased accordingly to maintain the same quality of muscle contractions. The NMES protocol consisted of 10 seconds of stimulation followed by 50 seconds of rest. This process was repeated for 10 repetitions across 2 sets, resulting in a total of 20 contractions, with the entire procedure lasting 20 minutes for each participant.^[44]

Figure 2.

Placement of electrodes and cups on the hamstring and quadriceps femoris muscles. Placement of stimulation electrodes and cupping devices on the hamstring and quadriceps femoris muscles. NMES was administered bilaterally with surface electrodes on both m. hamstring and m. quadriceps femoris. DCT cups were similarly positioned on the same muscle regions to ensure protocol consistency. DCT = dry cupping therapy, m. = musculus, NMES = neuromuscular electrical stimulation.

2.3.2. Dry cupping therapy (DCT) protocol

The DCT increases blood and lymph circulation around the targeted area.^[45] Typically, cups are applied in clusters of 4, 6, or 10 to the vacuumed target area for durations ranging from 5 to 20 minutes, or even longer.^[46] However, DCT sessions exceeding 20 minutes can result in complications due to the high vacuum pressure, potentially causing the epidermal layer to separate from the dermal base, and leading to discomfort such as pain, swelling, and tingling.^[47] Therefore, in this study, the duration of DCT was set to 20 minutes. The application was carried out bilaterally on the central areas of the m. hamstring and m. quadriceps femoris muscles, which form the anterior and posterior muscle groups of the thigh, using 4 number 6 cups.^[48]

2.4. Data collection

2.4.1. Wingate Anaerobic Test (WAnT) procedure

The Wingate Anaerobic Power Test (WAnT) was administered using a cycling ergometer (Monark 839E, Sweden) equipped with a computer interface to assess the participants’ lower body anaerobic performance. WAnT is the most popular submaximal cycling ergometer test in which individuals pedal as fast as possible against resistance determined by their body weight.^[49,50] During the test, participants pedaled without any load and, upon reaching their maximal pedaling speed, an external resistance corresponding to 7.5% of each participant’s body weight was applied. The participants then pedaled at high-speed for 30 seconds against this resistance. Once external resistance was applied, pedal revolutions were recorded every 5 seconds by the computer software.^[51] Power parameters, including absolute (W) and relative (W/kg), PP, MP, and fatigue index (FI, also referred to as anaerobic fatigue or fatigue rate), were calculated using the Wingate software program.

2.4.2. Rating of perceived exertion (RPE)

Perceived exertion is defined as the subjective effort, strain, discomfort, and fatigue experienced by an individual during exercise, and it is commonly used in sports practices.^[52] Measuring perceived exertion is highly beneficial, as it helps estimate maximal capacity, determine exercise intensity, and assess perceptual preference.^[53] In this study, participants were asked to rate their perceived exertion levels immediately after each test session using Borg’s 6 to 20 RPE scale. This scale was chosen because it is the most commonly used tool for assessing perceived exertion. Borg’s RPE is a numerical scale ranging from 6 to 20,^[54] where a rating of 6 indicates “no exertion at all,” with no physical or psychological impact, and a rating of 20 represents “maximum exertion,” indicating that the individual has reached their maximal capacity or maximal oxygen uptake.^[43]

2.5. Statistical analyses

The statistical analysis was conducted to investigate the effects of different application types (Control, NMES, and DCT) on various performance parameters, including PP, MP, FI, and RPE values. The analysis was performed using JASP software (version 10.2, University of Amsterdam). The data showed a normal distribution by considering Shapiro–Wilk test results, skewness, and kurtosis values (P > .05). Repeated measures ANOVA was conducted to analyze differences in anaerobic performance metrics (e.g., PP, MP, FI, perceived exertion) across the 3 conditions (Control, NMES, and DCT). This analysis was chosen due to the within-subjects design, allowing for the comparison of means across conditions while controlling for individual variability. Sphericity was analyzed by Mauchly’s test. Sphericity assumed values were considered by ensuring the assumption of sphericity. According to the classification of partial eta squared values, an ηp² of 0.01 to 0.06 is considered a small effect, 0.06 to 0.14 is a medium effect, and ηp² ≥ 0.14 is a large effect.^[55] Post hoc pairwise comparisons using the Tukey HSD test further confirmed the lack of significant differences between any pairs of application types for all parameters. Cohen’s d effect sizes for pairwise comparisons are classified as follows: a small effect is 0.2 to 0.5, a medium effect is 0.5 to 0.8, and a large effect is 𝑑 ≥ 0.8.^[56] Since the post hoc comparisons did not reveal any significant differences, Cohen’s d was not calculated for these comparisons. The P-value threshold for statistical significance was set at P ≤ .05.

3. Results

The demographic data of the participants is summarized as follows: The mean age of the participants was 24.17 years, with a standard deviation (SD) of 2.37 years. The average height of the participants was 172.63 cm, with a SD of 6.43 cm. The mean body mass was 69.09 kg, with a SD of 9.28 kg. The body mass index of the participants had a mean value of 23.12 kg/m², with a SD of 2.16 kg/m².

In Figure 3A, B, the repeated measures ANOVA revealed no significant effect of application type on PP (F(2, 22) = 0.5805, P = .568, ηp² = 0.050, small effect) or MP (F(2, 22) = 0.5140, P = .6051, ηp² = 0.045, small effect). These results suggest that the application types do not significantly influence PP and MP values.

Figure 3.

Effects of interventions on absolute peak power (PP) and mean power (MP). (A) Peak power (PP) and (B) mean power (MP) values in watts (W) across control, NMES, and DCT conditions (n = 12). Bars represent mean ± standard deviation (SD), with individual participant values overlaid. No statistically significant differences were observed between interventions (P > .05; repeated-measures ANOVA). PP = peak power, MP = mean power, SD = standard deviation, NMES = neuromuscular electrical stimulation, DCT = dry cupping therapy.

In Figure 4A, B, the results indicated that there was no significant effect of application type on PP (W/kg; F(2, 22) = 2.1583, P = .1394, ηp² = 0.164, medium effect) or MP (W/kg; F(2, 22) = 5.5956, P = .0108, ηp² = 0.337, large effect). post hoc pairwise comparisons using the Tukey HSD test further confirmed the lack of significant differences between any pairs of application types for both PP (W/kg) and MP (W/kg). Specifically, for PP (W/kg), no significant differences were found between CG and DCT (P = .3924), CG and NMES (P = .9998), or DCT and NMES (P = .4172). Similarly, for MP, no significant differences were observed between CG and DCT (P = .9951), CG and NMES (P = .1538), or DCT and NMES (P = .1441). Therefore, the analysis did not reveal any statistically significant differences in PP (W/kg) or MP (W/kg) among the 3 application types at the standard significance threshold of.

Figure 4.

Effects of interventions on relative peak power and mean power (W/kg). (A) Relative peak power (PP, W/kg) and (B) relative mean power (MP, W/kg) under control, NMES, and DCT conditions. Data are displayed as mean ± SD with individual values. A significant difference in MP was found between NMES and DCT (P < .05). Asterisks (*) indicate statistically significant comparisons (Tukey HSD post hoc test). PP = peak power, MP = mean power, SD = standard deviation, W/kg = watts per kilogram, NMES = neuromuscular electrical stimulation, DCT = dry cupping therapy.

In Figure 5B, B, the repeated measures ANOVA revealed that significant effects were found for FI (F(2, 22) = 4.0792, P = .0311, ηp² = 0.271, large effect) and RPE (F(2, 22) = 8.8846, P = .0015, ηp² = 0.447, large effect). These results suggest that the application types have a significant effect on FI and RPE values.

Figure 5.

Effects of interventions on fatigue index (FI) and rate of perceived exertion (RPE). (A) fatigue index (FI, %) and (B) rate of perceived exertion (RPE) scores under all 3 conditions. Data are presented as mean ± SD and individual participant values. Significant differences were identified between Control–NMES and NMES–DCT (P < .05). No difference was found between Control and DCT. Asterisks (*) denote significant group differences (Tukey HSD post hoc test). FI = fatigue index, RPE = rate of perceived exertion, SD = standard deviation, NMES = neuromuscular electrical stimulation, DCT = dry cupping therapy.

To further investigate these significant effects, post hoc pairwise comparisons were conducted using the Tukey HSD test. For FI, a significant difference was observed between CG and NMES (P = .0311), with a Cohen’s d of 0.44 (small to medium effect). Regarding the RPE values, significant differences were observed between CG and DCT (P = .0018), with a Cohen’s d of 0.74 (medium effect), and between DCT and NMES (P = .0005), with a Cohen’s d of 0.37 (small to medium effect).

4. Discussion

Recently, in addition to scientifically validated training methods for enhancing strength and physical performance, various supplementary techniques have been widely investigated. NMES and DCT are among these methods. The use of NMES or DCT champions in certain sports has sparked interest in whether these methods have a positive effect on performance. Based on this interest, the present study examined the effects of DCT and NMES on fatigue and perceived exertion in anaerobic performance in physically active individuals. The findings revealed that although the application methods did not significantly affect PP or MP in either absolute or relative terms, they had a notable impact on the FI and RPE values. A significant difference in RPE values was observed between the DCT and control groups (P = .0018) with a Cohen’s d of 0.74 (moderate effect) and between DCT and NMES (P = .0005) with a Cohen’s d of 0.37 (small to moderate effect). Regarding the FI values, a significant difference was detected between the NMES group and the control group (P = .0311) with a Cohen’s d of 0.44 (small to moderate effect).

In sedentary individuals, studies have shown both positive effects of NMES^[18,57–61] and a lack of improvement.^[62,63] The variation in results related to NMES may be due to the lack of standardization in test and training protocols. Additionally, NMES may have a greater impact on elite athletes compared to sedentary individuals because it is applied as a supplement to their regular training routines.^[64] Given that NMES did not significantly affect acute anaerobic performance in the present study, this outcome may be attributed to the fact that the participants were not active athletes. Similarly, the absence of beneficial effects of electrical stimulation has been observed in anaerobic field conditions, such as vertical jumps and sprints,^[65] as well as in aerobic variables, such as oxygen consumption.^[66]

The lack of measurable or consistent improvement in muscle strength and subsequent performance is partially due to methodological factors. For example, Martin et al^[67] emphasized the need for optimal stimulation intensity to maximize the muscle pump effect and support potential recovery benefits. Similarly, Grunovas et al^[68] recommended using stimulation intensity targeting the fibrillation of individual muscle fibers to reduce muscle ischemia. These findings suggest that low frequency electrical stimulation could have a beneficial effect, such as enhancing metabolite clearance.^[69] However, there is insufficient evidence that NMES has a short-term impact on various performance and physiological variables, such as aerobic, anaerobic, and neuromuscular parameters.

In contrast, NMES has been suggested to have a positive effect on increasing muscle strength and improving functional performance. A study by Calik et al^[17] found that both isometric exercises and electrical stimulation led to an increase in quadriceps femoris muscle strength, although no statistically significant difference was observed between the groups. This result suggests that the effects of NMES on muscle strength may be at least as effective as traditional exercises. Similar findings have been supported by studies that demonstrated an increase in isokinetic muscle strength following NMES application in both healthy individuals^[19] and post-anterior cruciate ligament surgery.^[22] da Cunha et al^[70] also found that incorporating NMES into the training programs of volleyball players contributed positively to their jumping ability and the strength of both the dominant and nondominant lower extremity muscles. Additionally, it was concluded that NMES can improve the functional condition of stimulated muscles.^[71]

There are also studies suggesting that NMES alone, without any accompanying physical exercise, is not effective in improving performance,^[72] and that when combined with voluntary training, NMES can be effective in activating high-threshold motor units.^[73–75] It has been proposed that the number of motor units activated during NMES is lower compared to voluntary contractions of the same intensity.^[76] NMES enhances muscle contraction strength through intracellular activities in the ionic membrane mechanisms of muscle stimulation and contraction without changes in neural processes. When comparing submaximal NMES with voluntary training, the peripheral changes resulting from NMES are less pronounced, likely due to differences in the number and types of motor units recruited in each method, which suggests that NMES plays a complementary role to voluntary training.^[72]

Considering that NMES does not have a positive effect on anaerobic performance, it has been recommended that NMES be combined with resistance training in a specialized and complementary approach to improve anaerobic power.^[77]

In this regard, it has been stated that a specific training period is necessary to improve performance before observing the beneficial effects of NMES. In a study conducted by Maffiuletti et al,^[78] it was found that after 4 weeks of combined NMES and standardized basketball training, there was an increase in maximal power performance. Similarly, in a study by Zory et al,^[79] a short-term NMES training protocol did not result in power increases; however, after a 4-week training period, a delayed increase in power was observed, alongside the normalization of contraction function over time. These findings suggest that the beneficial effects of NMES may emerge gradually over time.

DCT, by facilitating myofascial decompression, enhances vascular function, improves tissue oxygenation, and reduces oxidative stress through the inflammatory response.^[80–83] Despite the increasing popularity of DCT before sports competitions,^[84] there are very few studies in the literature investigating the physiological and performance-related effects of DCT. The limited studies that exist primarily focus on performance parameters such as joint range of motion, jumping ability, pain, functionality, recovery, and quality of life in athletes.^[31–34] In a study by Al-Horani et al,^[85] it was found that dry cupping applied before high-intensity exercise did not contribute to any performance or physiological improvements. In a similar study, the effect of DCT on aerobic and anaerobic capacity in athletes was examined, and it was found that DCT did not result in a significant difference in either aerobic or anaerobic performance between groups.^[86] These findings are consistent with the results of our study.

In the literature, it has been emphasized that at least 1 full familiarization trial is required to increase the reliability of power output measurements.^[87] In the present study, a familiarization protocol was implemented before the 30-second Wingate test. Additionally, to determine whether DCT could be an effective strategy for enhancing anaerobic performance, participants were instructed to increase their sleep duration, regulate food and fluid intake, and avoid ergogenic substances, alcohol, and intense exercise, as these factors have been suggested to affect WAnT performance in previous studies.^[88,89] To eliminate the psychological effect of DCT, participants were given neutral feedback regarding the effectiveness of the application. Consequently, it was concluded that DCT, when applied within 24 hours or less, did not provide any positive performance effect on Wingate’s anaerobic performance.

Our study found that DCT had a notable impact on perceived exertion levels. This result is thought to be due to the reduction in muscle soreness and the accelerated recovery process associated with DCT, which led to a greater effect on perceived exertion compared to EMS application.^[84]

4.1. Limitations

The present study has several limitations that may impact the generalizability and interpretation of the findings. First, the study was conducted with non-athlete participants, which limits the applicability of the results to active or elite athletes, as trained individuals may respond differently to NMES and DCT due to higher baseline fitness and adaptive capacities. Additionally, our study focused on the immediate, acute effects of NMES and DCT, with each application lasting 20 minutes, which may have been insufficient to produce measurable changes in anaerobic performance metrics like PP and MP values. Future studies with prolonged or repeated application periods could offer insights into potential chronic adaptations from these interventions. We also measured a limited range of outcomes focused on anaerobic performance, while additional physiological markers, such as muscle oxygenation, blood lactate levels, and recovery biomarkers, could provide a deeper understanding of NMES and DCT’s impact on anaerobic performance. Furthermore, although we standardized the application protocols, individual differences in response to stimulation (e.g., variations in muscle contractility or skin sensitivity) might have influenced the outcomes, suggesting that customizing protocols to individual tolerance may yield more accurate assessments. Moreover, perceived effects may have been influenced by participants’ expectations or previous experiences with NMES and DCT, despite neutral feedback being provided; a double-blind or placebo-controlled design could help mitigate potential biases arising from participant expectations. Additionally, while efforts were made to control external factors such as warm-up routines and testing time, variables like participants’ sleep, hydration, and nutrition could also have influenced performance, indicating the need for more rigorous control of these factors in future research. The last limitation of this study is the use of a quasi-experimental crossover design. While this design allows each participant to serve as their control, it lacks randomization in the order of interventions, which may introduce potential order effects. Although a 48-hour rest period was implemented to minimize carryover effects, future studies could consider using a fully randomized crossover design to further control for any residual effects.

4.2. Practical applications

This study provides valuable insights for sports coaches, athletic trainers, and rehabilitation professionals. While NMES and DCT did not produce significant short-term improvements in peak and mean anaerobic power, both interventions were found to impact the FI and reduce perceived exertion levels. These findings suggest that NMES and DCT could be incorporated into athlete recovery protocols, especially for sports that require high anaerobic output and resilience to fatigue, such as sprinting, cycling, and combat sports. By lowering perceived exertion and improving fatigue resistance, these methods may aid in maintaining training intensity and consistency over time. Integrating NMES or DCT after intense training or competition could help athletes manage muscle soreness and accelerate recovery, potentially reducing downtime and enhancing performance continuity. For practical implementation, practitioners may consider using these methods in combination with existing recovery techniques, such as stretching and low-intensity aerobic exercise, to optimize recovery routines. Future studies exploring optimal application frequency, duration, and timing could further clarify how best to use NMES and DCT for maximum recovery and performance benefits in different athletic contexts.

5. Conclusions

In this study, it was concluded that DCT and NMES applied to the major lower extremity muscle groups did not have a short-term effect on PP and MP values during the participants’ maximal cycling all-out anaerobic test. However, both methods had a notable impact on the FI and RPE values. This study is unique as it is the first to investigate whether NMES and DCT, a traditional and complementary medicine method used for various health issues since ancient times, have had any positive effect on the development of anaerobic performance, which is considered a crucial prerequisite for success in many sports disciplines. Therefore, the results are considered to be highly significant for the sports science literature. Nonetheless, future studies could enhance the generalizability of these findings by investigating the effects of NMES and DCT on trained athletes in different sports disciplines or exploring their chronic effects following a training program.

Acknowledgments

We thank the participants for their participation in this study.

Author contributions

Conceptualization: İbrahim Can, Gökhan Yerlikaya, Valentina Stefanica, Halil İbrahim Ceylan.

Data curation: Serdar Bayrakdaroğlu, Ender Ali Uluç.

Formal analysis: Gökhan Yerlikaya, Ender Ali Uluç.

Funding acquisition: Recep Fatih Kayhan.

Investigation: Seda Yalçin, Recep Fatih Kayhan, Halil İbrahim Ceylan.

Methodology: İbrahim Can.

Project administration: Seda Yalçin.

Resources: Gökhan Yerlikaya, Recep Fatih Kayhan, Valentina Stefanica.

Software: Serdar Bayrakdaroğlu.

Supervision: Seda Yalçin, Ender Ali Uluç, Halil İbrahim Ceylan.

Validation: Seda Yalçin, Serdar Bayrakdaroğlu.

Visualization: Ender Ali Uluç.

Writing – original draft: İbrahim Can, Gökhan Yerlikaya, Recep Fatih Kayhan, Valentina Stefanica, Halil İbrahim Ceylan.

Writing – review & editing: İbrahim Can, Gökhan Yerlikaya, Valentina Stefanica, Halil İbrahim Ceylan.