Handcycling with concurrent lower body low-frequency electromyostimulation significantly increases acute oxygen uptake in elite wheelchair basketball players: an acute crossover trial.

OBJECTIVE: Wheelchair basketball (WCB) demands high-intensity training due to its intermittent nature. However, acute oxygen uptake (V˙O2) in handcycling is restricted. Combining handcycling with low-frequency electromyostimulation (LF-EMS) may enhance V˙O2 in elite WBC athletes. DESIGN: Randomized crossover trail. SUBJECTS: Twelve German national team WCB players (age: 25.6 [5.6] years, height: 1.75 [0.16] m, mass: 74.0 [21.7] kg, classification: 2.92 [1.26]). METHOD: Participants underwent 2×5 min of handcycling (60 rpm, ¾ bodyweight resistance in watts) (HANDCYCLE) and 2×5 min of handcycling with concurrent LF-EMS (EMS_HANDCYCLE). LF-EMS (4Hz, 350µs, continuous stimulation) targeted gluteal, quadriceps, and calf muscles, adjusted to individual pain thresholds (buttocks: 69.5 [22.3] mA, thighs: 66.8 [20.0] mA, calves: 68.9 [31.5] mA). RESULTS: Significant mode-dependent differences between HANDCYCLE and EMS_HANDCYCLE were found in V˙O2 (17.60 [3.57] vs 19.23 [4.37] ml min-1 kg-1, p = 0.001) and oxygen pulse (16.69 [4.51] vs 18.41 [5.17] ml, p = 0.002). ΔLactate was significantly lower in HANDCYCLE (0.04 [0.28] vs 0.31 [0.26] mmol l-1). Although perceived effort did not differ (p = 0.293), discomfort was rated lower in HANDCYCLE (1.44 [1.28] vs 3.94 [2.14], p = 0.002). CONCLUSION: LF-EMS applied to the lower extremities increases oxygen demand during submaximal handcycling. Thus, longitudinal application of LF-EMS should be investigated as a potential training stimulus to improve aerobic capacity in wheelchair athletes.

Effects of Four Weeks of Static vs. Dynamic Bodyweight Exercises with Whole-Body Electromyostimulation on Jump and Strength Performance: A Two-Armed, Randomized, Controlled Trial.

The combination of strength training with complementary whole-body electromyostimulation (WB-EMS) and plyometric exercises has been shown to increase strength and jumping performance in athletes. In elite sport, however, the mesocycles of training are often organized according to block periodization. Furthermore, WB-EMS is often applied onto static strength exercises, which may hamper the transfer into more sport-specific tasks. Thus, this study aimed at investigating whether four weeks of strength training with complementary dynamic vs. static WB-EMS followed by a four-week block of plyometric training increases maximal strength and jumping performance. A total of n = 26 (13 female/13 male) trained adults (20.8 ± 2.2 years, 69.5 ± 9.5kg, 9.7 ± 6.1h of training/w) were randomly assigned to a static (STA) or volume-, load- and work-to-rest-ratio-matched dynamic training group (DYN). Before (PRE), after four weeks (three times weekly) of WB-EMS training (MID) and a subsequent four-week block (twice weekly) of plyometric training (POST), maximal voluntary contraction (MVC) at leg extension (LE), leg curl (LC) and leg press machines (LP) and jumping performance (SJ, Squat Jump; CMJ, counter-movement-jump; DJ, drop-jump) were assessed. Furthermore, perceived effort (RPE) was rated for each set and subsequently averaged for each session. MVC at LP notably increased between PRE and POST in both STA (2335 ± 539 vs. 2653 ± 659N, standardized mean difference [SMD] = 0.528) and DYN (2483 ± 714N vs. 2885 ± 843N, SMD = 0.515). Reactive strength index of DJ showed significant differences between STA and DYN at MID (162.2 ± 26.4 vs. 123.1 ± 26.5 cm·s-1, p = 0.002, SMD = 1.478) and POST (166.1 ± 28.0 vs. 136.2 ± 31.7 cm·s-1, p = 0.02, SMD = 0.997). Furthermore, there was a significant effect for RPE, with STA rating perceived effort higher than DYN (6.76 ± 0.32 vs. 6.33 ± 0.47 a.u., p = 0.013, SMD = 1.058). When employing a training block of high-density WB-EMS both static and dynamic exercises lead to similar adaptations.

Corrigendum: Position statement and updated international guideline for safe and effective whole-body electromyostimulation training-the need for common sense in WB-EMS application.

[This corrects the article DOI: 10.3389/fphys.2023.1174103.].

Position statement and updated international guideline for safe and effective whole-body electromyostimulation training-the need for common sense in WB-EMS application.

Whole-Body Electromyostimulation (WB-EMS) is a training technology that enables simultaneous stimulation of all the main muscle groups with a specific impulse intensity for each electrode. The corresponding time-efficiency and joint-friendliness of WB-EMS may be particularly attractive for people unable or unmotivated to conduct (intense) conventional training protocols. However, due to the enormous metabolic and musculoskeletal impact of WB-EMS, particular attention must be paid to the application of this technology. In the past, several scientific and newspaper articles reported severe adverse effects of WB-EMS. To increase the safety of commercial non-medical WB-EMS application, recommendations "for safe and effective whole-body electromyostimulation" were launched in 2016. However, new developments and trends require an update of these recommendations to incorporate more international expertise with demonstrated experience in the application of WB-EMS. The new version of these consensus-based recommendations has been structured into 1) "general aspects of WB-EMS", 2) "preparation for training", recommendations for the 3) "WB-EMS application" itself and 4) "safety aspects during and after training". Key topics particularly addressed are 1) consistent and close supervision of WB-EMS application, 2) mandatory qualification of WB-EMS trainers, 3) anamnesis and corresponding consideration of contraindications prior to WB-EMS, 4) the participant's proper preparation for the session, 5) careful preparation of the WB-EMS novice, 6) appropriate regeneration periods between WB-EMS sessions and 7) continuous interaction between trainer and participant at a close physical distance. In summary, we are convinced that the present guideline will contribute to greater safety and effectiveness in the area of non-medical commercial WB-EMS application.

Effects of electromyostimulation on performance parameters in sportive and trained athletes: A systematic review and network meta-analysis.

This systematic review and network meta-analysis aimed to evaluate the effectiveness of different electromyostimulation (EMS) interventions on performance parameters in athletes. The research was conducted until May 2021 using the online databases PubMed, Web of Science, Cochrane and SPORTDiscus for studies with the following inclusion criteria: (a) controlled trials, (b) EMS trials with at least one exercise and/or control group, (c) strength and/or jump and/or sprint and/or aerobic capacity parameter as outcome (d) sportive/trained subjects. Standardized mean differences (SMD) with 95% confidence interval (CI) and random effects models were calculated. Thirty-six studies with 1.092 participants were selected and 4 different networks (strength, jump, sprint, aerobic capacity) were built. A ranking of different exercise methods was achieved. The highest effects for pairwise comparisons against the reference control "active control" were found for a combination of resistance training with superimposed EMS and additional jump training (outcome strength: 4.43 SMD [2.15; 6.70 CI]; outcome jump: 3.14 SMD [1.80; 4.49 CI]), jump training with superimposed whole-body electromyostimulation (WB-EMS) (outcome sprint: 1.65 SMD [0.67; 2.63 CI]) and high intensity bodyweight resistance training with superimposed WB-EMS (outcome aerobic capacity: 0.83 SMD [-0.49; 2.16 CI]). These findings indicate that the choice of EMS-specific factors such as the application mode, the combination with voluntary activation, and the selection of stimulation protocols has an impact on the magnitude of the effects and should therefore be carefully considered, especially in athletes. Superimposed EMS with relatively low volume, high intensity and outcome-specific movement patterns appeared to positively influence adaptations in athletes.HighlightsKey performance parameters such as maximal strength, jump height and sprint time can be increased by adequate EMS intervention programs in already well-trained athletes.The effectiveness of EMS training in athletes is highly dependent on the selected EMS method. Volume, intensity, exercise and movement specificity play a crucial role for the efficiency of the training.The most effective option for athletes appears to be a combination of superimposed EMS with relatively low EMS volume, high intensity, and movement-specific exercise pattern.

Similar Pain Intensity Reductions and Trunk Strength Improvements Following Whole-Body Electromyostimulation vs. Whole-Body Vibration vs. Conventional Back-Strengthening Training in Chronic Non-specific Low Back Pain Patients: A Three-Armed Randomized Controlled Trial.

The aim of this multicenter trial was to compare the effects of whole-body electromyostimulation (WB-EMS) and whole-body vibration (WBV) with conventional back-strengthening training (CT) on changes in mean back pain intensity (MPI) and trunk strength in patients suffering from chronic non-specific low back pain (CNLBP). Two-hundred and forty CNLBP patients (40-70 years; 62% female) were randomly assigned to three intervention arms (WB-EMS: n = 80 vs. WBV: n = 80 vs. CT: n = 80). All training intervention programs were performed for 12 weeks in their usual commercial training setting. Before and during the last 4 weeks of the intervention, MPI was recorded using a 4-week pain diary. Additionally, maximal isometric trunk extension and -flexion strength was assessed on the BackCheck® machine. A moderate but significant decrease of MPI was observed in all groups (WB-EMS: 29.7 ± 39.1% (SMD 0.50) vs. WBV: 30.3 ± 39.3% (SMD 0.57) vs. CT: 30.5 ± 39.6% (SMD 0.59); p < 0.001). Similar findings were observed for maximal isometric strength parameters with a significant increase in all groups (extension: WB-EMS: 17.1 ± 25.5% vs. WBV: 16.2 ± 23.6% vs. CT: 21.6 ± 27.5%; p < 0.001; flexion: WB-EMS: 13.3 ± 25.6% vs. WBV: 13.9 ± 24.0% vs. CT: 13.9 ± 25.4%; p < 0.001). No significant interaction effects for MPI (p = 0.920) and strength parameters (extension: p = 0.436; flexion: p = 0.937) were observed. WB-EMS, WBV, and CT are comparably effective in improving MPI and trunk strength. However, training volume of WB-EMS was 43 or 62% lower, compared with CT and WBV.

Effects of Whole-Body Electromyostimulation on Strength-, Sprint-, and Jump Performance in Moderately Trained Young Adults: A Mini-Meta-Analysis of Five Homogenous RCTs of Our Work Group.

Background: Whole-body electromyostimulation (WB-EMS) gained increasing interest in sports within recent years. However, few intervention studies have examined the effects of WB-EMS on trained subjects in comparison to conventional strength training. Objective: The aim of the present mini-meta-analysis of 5 recently conducted and published randomized controlled WB-EMS trails of our work group was to evaluate potentially favorable effects of WB-EMS in comparison to conventional strength training. Methods: We included parameter of selected leg muscle's strength and power as well as sprint and jump performance. All subjects were moderately trained athletes [>2 training sessions/week, >2 years of experience in strength training; experimental group (n = 58): 21.5 ± 3.3 y; 178 ± 8 cm; 74.0 ± 11 kg; control group (n = 54): 21.0 ± 2.3 y; 179.0 ± 9 cm; 72.6 ± 10 kg]. The following WB-EMS protocols were applied to the experimental group (EG): 2 WB-EMS sessions/week, bipolar current superimposed to dynamic exercises, 85 Hz, 350 µs, 70% of the individual pain threshold amperage. The control groups (CG) underwent the same training protocols without WB-EMS, but with external resistance. Results: Five extremely homogenous studies (all studies revealed an I 2 = 0%) with 112 subjects in total were analyzed with respect to lower limb strength and power in leg curl, leg extension and leg press machines, sprint-and jump performance. Negligible effects in favor of WB-EMS were found for Fmax of leg muscle groups [SMD: 0.11 (90% CI: -0.08, 0.33), p = 0.73, I 2 = 0%] and for CMJ [SMD: 0.01 (90% CI: -0.34, 0.33), p = 0.81, I 2 = 0%]. Small effects, were found for linear sprint [SMD: 0.22 (90% CI: -0.15, 0.60), p = 0.77, I 2 = 0%] in favor of the EMS-group compared to CON. Conclusion: We conclude that WB-EMS is a feasible complementary training stimulus for performance enhancement. However, additional effects on strength and power indices seem to be limited and sprint and jump-performance appear to be benefiting only slightly. Longer training periods and more frequent application times and a slightly larger stimulus could be investigated in larger samples to further elucidate beneficial effects of WB-EMS on performance parameters in athletes.

The Effects of Superimposed Whole-Body Electromyostimulation During Short-Term Strength Training on Physical Fitness in Physically Active Females: A Randomized Controlled Trial.

The aim of this study was to compare the effects of short-term strength training with and without superimposed whole-body electromyostimulation (WB-EMS) on straight sprinting speed (SSS), change of direction speed (CODS), vertical and horizontal jumping, as well as on strength and power in physically active females. Twenty-two active female participants (n = 22; mean ± SD: age: 20.5 ± 2.3 years; height: 171.9 ± 5.5 cm; body mass: 64.0 ± 8.2 kg; strength training experience 5.1 ± 3.6 years) were randomly assigned to two groups: strength training (S) or strength training with superimposed WB-EMS (S+E). Both groups trained twice a week over a period of 4 weeks and differed in the application of free weights or WB-EMS during four strength (e.g., split squats, glute-ham raises) and five sprinting and jumping exercises (e.g., side and box jumps, skippings). The WB-EMS impulse intensity was adjusted to 70% of individual maximal sustainable pain. SSS was tested via 30-m sprinting, CODS by a T-run, vertical and horizontal jumping using four different jump tests at pre-, post-, and retests. Maximal strength (Fmax) and power (Pmax) testing procedures were conducted on the Leg Press (LP), Leg Extension (LE), and Leg Curl (LC) machine. Significant time × group interaction effects revealed significant decreases of contact time of the Drop Jump and split time of CODS (p ≤ 0.043; η p 2 = 0.15-0.25) for S (≤ 11.6%) compared to S+E (≤ 5.7%). Significant time effects (p < 0.024; η p 2 = 0.17-0.57) were observed in both groups for SSS (S+E: ≤6.3%; S: ≤8.0%) and CODS (S+E: ≤1.8%; S: ≤2.0%) at retest, for jump test performances (S+E: ≤13.2%; S: ≤9.2%) as well as Fmax and Pmax for LE (S+E: ≤13.5%; S: ≤13.3%) and LC (S+E: ≤18.2%; S: ≤26.7%) at post- and retests. The findings of this study indicate comparable effects of short-term strength training with and without superimposed WB-EMS on physical fitness in physically active females. Therefore, WB-EMS training could serve as a reasonable but not superior alternative to classic training regimes in female exercisers.

Effects of an Eight-Week Superimposed Submaximal Dynamic Whole-Body Electromyostimulation Training on Strength and Power Parameters of the Leg Muscles: A Randomized Controlled Intervention Study.

The purpose of this study was to assess the effects of dynamic superimposed submaximal whole-body electromyostimulation (WB-EMS) training on maximal strength and power parameters of the leg muscles compared with a similar dynamic training without WB-EMS. Eighteen male sport students were randomly assigned either to a WB-EMS intervention (INT; n = 9; age: 28.8 (SD: 3.0) years; body mass: 80.2 (6.6) kg; strength training experience: 4.6 (2.8) years) or a traditional strength training group (CON; n = 9; age: 22.8 (2.5) years; body mass: 77.6 (9.0) kg; strength training experience: 4.5 (2.9) years). Both training intervention programs were performed twice a week over a period of 8 weeks with the only difference that INT performed all dynamic exercises (e.g., split squats, glute-ham raises, jumps, and tappings) with superimposed WB-EMS. WB-EMS intensity was adjusted to 70% of the individual maximal tolerable pain to ensure dynamic movement. Before (PRE), after (POST) and 2 weeks after the intervention (FU), performance indices were assessed by maximal strength (Fmax) and maximal power (Pmax) testing on the leg extension (LE), leg curl (LC), and leg press (LP) machine as primary endpoints. Additionally, vertical and horizontal jumps and 30 m sprint tests were conducted as secondary endpoints at PRE, POST and FU testing. Significant time effects were observed for strength and power parameters on LE and LC (LE Fmax +5.0%; LC Pmax +13.5%). A significant time × group interaction effect was merely observed for Fmax on the LE where follow-up post hoc testing showed significantly higher improvements in the INT group from PRE to POST and PRE to FU (INT: +7.7%, p < 0.01; CON: +2.1%). These findings indicate that the combination of dynamic exercises and superimposed submaximal WB-EMS seems to be effective in order to improve leg strength and power. However, in young healthy adults the effects of superimposed WB-EMS were similar to the effects of dynamic resistance training without EMS, with the only exception of a significantly greater increase in leg extension Fmax in the WB-EMS group.

When neuroscience gets wet and hardcore: neurocognitive markers obtained during whole body water immersion.

Neutral buoyancy facilities are used to prepare astronauts and cosmonauts for extra vehicular activities e.g. on-board of the International Space Station. While previous studies indicated a decrease in cognitive performance in an under water setting, they have only provided behavioural data. This study aimed to review whether recording of electro cortical activity by the use of electroencephalography (EEG) is possible in an under water setting and if so, to identify the influence of water immersion at a depth of 4 m on neurocognitive markers. Ten male subjects performed a cognitive choice-reaction times (RT) task that progressed through five levels of increasing difficulty on land and when submerged 4 m under water. N200 latency and amplitude in the occipital and frontal areas were measured, and baseline cortical activity was measured during rest in both conditions. Neither RT nor amplitude or latency of the N200 showed any significant changes between the land and the under water conditions. Also theta, alpha and beta frequencies showed no differences between the two conditions. The data provided in this study demonstrate the possibility of recording EEG even under the extreme conditions of full body water immersion. The lack of cognitive impairment in RT and N200 in the under water condition may be explained by the fact that only experienced divers participated in the study. As a proof of principle, this study generates many new experimental possibilities that will improve our understanding of cognitive processes under water.