I'm a bodybuilder – do I need a muscle stimulator?
I’ll start with a reader’s question: “I read about electrical stimulation and would like some advice. I'm a bodybuilder and my primary goals are increasing muscle mass and relaxing the muscles. Please help me choose a device.”
This question may interest many – so I’m writing a detailed answer. For a bodybuilder a muscle stimulator does not replace barbell training, and does not provide rapid muscle mass gains. But there are specific situations where it offers things you cannot achieve with other tools. In this article I’ll walk you through six such situations – based on realistic evidence, without “instant miracle” marketing.
Key idea
For the bodybuilder the muscle stimulator is an training-support tool, not a replacement. Modern literature (Happ et al. 2022, 19 RCTs) indicates that EMS produces strength gains similar to conventional resistance training when volume is matched1, but it does NOT give more than classic strength training. The real value is: (1) warm-up and injury prevention, (2) recovery, (3) targeted development of lagging muscle groups, and (4) maintenance during injury – these are areas where other tools don’t provide the same extra benefit.
The muscle stimulator’s “reach” – what to expect and what not to
The body contains roughly 350 striated muscles, which form larger groups: forearm, upper arm, chest, back and spinal stabilizers, trunk, abdomen, glutes, thigh, and lower leg. Sport muscle stimulators are typically suitable for treating one (maximum two) larger muscle groups at a time – you cannot work the entire body simultaneously.
This is an important limitation: the stimulator does not replace and cannot substitute resistance training. Think of it as a technical accessory – like the right sports shoe or a gym machine. It adds something, but the hard work is still your responsibility.
Like a sports shoe
Many people still sweat in cotton T-shirts instead of breathable fabrics – likewise, many still train without a stimulator. No one can skip hard training, but the stimulator can provide advantages that a person training only “traditionally” will not get: faster recovery, more effective warm-up, and a tool to break stagnation. You can decide whether you prefer progress or sticking with your old routine.
How does the brain regulate muscle fibers? – The Henneman principle
To understand why a muscle stimulator can be useful for a bodybuilder, first you need the Henneman “size principle”:
- Type I fibers (slow, endurance): activated first in every movement. They are thinner and do not add much mass – mainly for sustained efforts.
- Type IIa fibers (intermediate, mixed): recruited when effort exceeds roughly 50% of maximum. They have mixed properties and are typical for endurance-strength work.
- Type IIb fibers (fast, explosive): the fibers that contribute most to mass – BUT they are only voluntarily recruited when effort exceeds about 80% of your maximum.
This explains why your arm circumference won’t increase from curling 5 kg even with tens of thousands of repetitions – you only “tickle” Type I fibers. That’s why bodybuilders use low-repetition, heavy sets.
Modern nuance: EMS recruitment works differently
Modern literature (Maffiuletti 2010, Bickel 2011) shows that EMS DOES NOT follow the Henneman size principle – recruitment with EMS is not selective, is spatially fixed and temporally synchronized.4, 7 That means EMS activates muscles differently than the classic “small weight → Type I, heavy weight → Type IIb” sequence. This can be both an advantage (you can bypass voluntary system limits) and a limitation (it does not provide immediate fiber-specific selection). The true effect is in CHRONIC adaptation – weeks to months of regular use.
6 specific situations when EMS is worth using as a bodybuilder
In the six situations below the stimulator gives bodybuilders benefits they can’t get with other tools. Each has a concrete physiological explanation:
Muscle mass can be developed with heavy loads – which significantly stresses muscles and even more so the tendons. Tendons have poorer blood flow than muscles, so warming them is harder. Without warm-up ligaments and bone attachment points can be overloaded – inflammation may occur, leading to injuries (tennis elbow, tenosynovitis, Achilles tendinopathy, plantar fascia inflammation, piriformis syndrome, etc.).
A 15–20 minute pre-training muscle stimulation warm-up increases blood flow to muscle and associated tendons, warming and making the muscle more elastic. In a 2025 clinical trial passive warm-up using HVPC stimulation measurably increased jump performance compared to control – indicating EMS warm-up truly “prepares” the muscle.3
Heavy training leaves metabolites (lactate, lactic acid, hydrogen ions) in the muscle – these cause fatigue, stiffness, and sometimes pain. Improving blood flow helps clear these metabolites.
The effect of EMS recovery is mixed: a 2014 systematic review (13 studies) found it produces better lactate clearance than passive rest, but active aerobic recovery (e.g., light cycling) is generally BETTER.5 In a 2009 clinical trial with swimmers, active swimming after exercise produced significantly lower lactate after 20 minutes than EMS.6
What does this mean for you? EMS recovery is useful when active aerobic recovery isn’t possible (busy training day, late at night, travel). If possible, light cycling or swimming for 20–30 minutes is preferable. EMS is not a miracle, but it is better than passive rest.
Many experience that a specific muscle group (e.g., inner head of the biceps, upper chest, calf) won’t develop as well as others despite conventional training. Often the issue is that the target muscle is hard to isolate voluntarily – surrounding muscles take over the load.
With electrode positioning the stimulator lets you FOCUS precisely on the desired muscle group. Modern literature shows EMS produces similar strength gains to resistance training when volume is matched – so if you add a targeted EMS protocol to a lagging muscle alongside conventional training, you can get a combined effect.1, 2
A 2012 systematic review found that in elite athletes (89 studies) EMS training added measurable improvements in strength, jump and sprint performance within 3–6 weeks when combined with traditional training.8
Imagine: during a strength-focused session you squat and your knee starts to hurt the next day. You think, “It’s from yesterday, I’ll push through.” You keep training and after 2–3 weeks realize it’s an overuse injury that needs rest. If you rest for 2–3 weeks you lose the gains of the prior 3–4 months.
Here EMS helps: while resting the joint (i.e., avoiding traditional movements that load the knee), stimulation maintains the condition of your leg muscles. Your thigh won’t atrophy because the muscle is regularly contracting. Once the injury heals and you resume training, you can practically continue where you left off.
This is especially important in ACL rehab: a 2022 clinical trial (Labanca et al.) found that early superimposed NMES after surgery produced better isokinetic strength and functional hop-test results than standard rehab.9
Muscle stimulation was originally developed as a medical, hospital treatment for restoring injured muscles. In sports injury it does not move the joint, so you can start muscle-preserving treatments a few days after most tendon, ligament, joint capsule, or cartilage injuries.
After a strain or tear you usually wait 3–4 days for bleeding to subside – then a gentle regenerative program increases blood and lymph circulation, delivering nutrients to the injured area and speeding fiber restoration. Important: work with your treating physician or physiotherapist’s approval, because too-early or too-intense stimulation can worsen the condition.
High-level athletes preparing for competition with multiple daily sessions face a real issue when traveling long distances: on a 20–30 hour flight muscles stiffen, and a two-day break affects performance. In such cases the stimulator is invaluable: it fits in your pocket, can be used on the plane or at the hotel, and maintains your most important muscles while you travel.
ActionNOW – active training and EMS simultaneously (especially for bodybuilders)
The ActionNOW program group available in Globus devices offers a unique opportunity specifically for bodybuilders: you can use electrical stimulation not separately, but DURING the exercise. You work with voluntary force and electrical contraction simultaneously – this is the so-called “superimposed” protocol, the best-documented form of EMS in modern literature.2
As a bodybuilder it is particularly useful in the following situations:
- Targeted training of a lagging muscle: e.g., if the inner head of your biceps isn’t developing, ActionNOW lets you activate extra fibers during the biceps contraction
- Injury prevention during maximum-load exercises: the synchronized contraction is more controlled and the muscle is “better prepared”
- Cleaner technique under heavy loads: stimulator’s extra activation helps maintain targeted muscle recruitment
For the detailed ActionNOW user guide see the EMS training programs and their application article.
See it in action – Muscle stimulation in practice
In this video I show how simple muscle stimulation can be. Proper electrode placement and program selection are also shown in detail:
What do studies say about EMS use in bodybuilding?
“Does it give the same strength gains as weight training?”
Volume-matched studies say yes. A 2022 systematic review and meta-analysis (19 RCTs) found EMS training produces essentially the same strength development as traditional resistance training (effect size 0.023 – i.e., no difference).1 This means EMS works, but it does NOT add extra beyond weight training – the combination (superimposed) brings additional benefits.
“What does EMS give elite athletes?”
A 2012 systematic review (Filipovic et al., 89 studies) found that in elite trained athletes 3–6 weeks of EMS training added measurable improvements: isometric strength, dynamic strength, explosive power, vertical jump, and sprint times all improved.8 Nuance: study protocols vary widely (different devices, frequencies, durations), so means mask methodological differences.
“What’s the best way to use it?”
The 2023 network meta-analysis by Micke et al. (36 RCTs, 1,092 athletes) found the highest effect sizes from SUPERIMPOSED protocols – that is, when EMS is used ALONGSIDE, not instead of, traditional training.2 The Globus ActionNOW program group exactly implements this approach for home use.
“What about recovery? Will I really recover faster?”
Partly. The 2014 Malone-SR (13 studies) found EMS recovery is better than passive rest, but active aerobic recovery (light swimming, cycling) generally yields better lactate clearance.5 A 2009 clinical trial showed active swim recovery produced lower lactate than EMS in swimmers.6 So: better than passive rest, but not a miracle.
“When can I start EMS after an injury?”
After surgery usually wait 2–3 weeks for wound healing, then start gently. A 2022 clinical trial (Labanca et al.) found early superimposed NMES after ACL reconstruction improved isokinetic strength and functional hop-test results compared to standard rehab.9 For strains/tears you can usually start a gentle regenerative program after 3–4 days – always with your treating physician’s approval.
The gist for bodybuilders – briefly
EMS training is meant to supplement traditional resistance training – combined use adds value. Warm-up, recovery, targeting lagging muscles, and maintenance during injury are the best application areas. Claims like “instant muscle mass increase” or “more effective than every other method” are NOT evidence-supported.
Device selection for bodybuilders
A good device for a bodybuilder should: (1) be 4-channel (so you can place 8 electrodes over a full large muscle group), (2) include Hypertrophy / Max strength / Explosive power programs, (3) include Warm-up / Recovery / Muscle stiffness relief programs, and (4) ideally include the ActionNOW superimposed program group.
Globus Premium 400
4-channel multifunction device with a built-in Sport program group. Warm-up, hypertrophy, max strength, recovery and muscle stiffness relief – everything a basic bodybuilder needs. Entry-level, good value for money.
Sport Pro line: Cycling / Runner / Triathlon / Soccer / Champion
Sport-specific 4-channel stimulators. Although sport-focused, they are ideal for bodybuilders thanks to detailed parameter fine-tuning. The Champion or Triathlon Pro are the most versatile choices.
Globus Genesy 600 / Genesy 1500 / Genesy 3000
Top-range Globus multifunction models with hundreds of programs – ActionNOW, Kotz, and the full Sport program group. Clinical-level parameter fine-tuning if you take EMS training seriously.
My advice for bodybuilders
Usually the Premium 400 or any Sport (Runner Pro, Cycling Pro, Soccer Pro, Triathlon Pro, The Champion) device is sufficient. They contain similar sport programs that fit any training routine. If you are serious and want top-tier features (ActionNOW, Kotz, parameter fine-tuning), the Genesy 1500 is recommended. The Genesy 1500 and Genesy 3000 include many functions more relevant to therapists or severe post-injury rehab. You don't need the flagship for training – consistency matters more than program count.
Before you start an EMS routine as a bodybuilder
EMS is contraindicated or requires specialist consultation in the following situations:
- Implanted pacemaker, ICD or other active implant – current may interfere with the device.
- Pregnancy – abdominal and lumbar treatments are forbidden in any stage of pregnancy.
- Epilepsy or other seizure disorders – stimulation may trigger seizures.
- Acute muscle rupture, fresh strain (first 3–4 days) – wait for bleeding to stop before starting; then begin a gentle recovery program.
- Recently operated area – wait for wound healing (minimum 2–3 weeks) and only start with medical approval.
- Active deep vein thrombosis (DVT) – urgent medical care needed; do not start home treatment.
- Active malignant tumor in the treatment area – avoid the affected region.
- Skin disease, injury or loss of sensation in the treatment area – the skin should be intact and sensate.
- Acute fever or infectious disease – wait for recovery.
- Severe cardiovascular disease – for arrhythmia or heart failure obtain cardiology approval.
Further reading
For the full contraindication list read our article on electrical treatment contraindications.
Frequently asked questions
No. The 2022 Happ meta-analysis found EMS produces similar strength gains to resistance training when volume is matched1, BUT traditional resistance training remains fundamental for full movement coordination, neural adaptations, and cardiovascular development. The best strategy is EMS alongside resistance training (superimposed protocol, e.g., ActionNOW).2
Main programs (hypertrophy / max strength / ActionNOW) 2–3 times weekly – similar to traditional strength training. Plus one recovery session (15–20 minutes) after each workout, and a warm-up (10–15 minutes) before each session. Too frequent hypertrophy / max strength sessions impair recovery – gradual progression is essential.
Compared to passive rest, yes; compared to active aerobic recovery (light cycling, swimming) generally no.5, 6 EMS recovery is advantageous when active recovery isn’t possible (travel, late evening, busy day). There is no instant miracle, but it’s better than doing nothing.
Partly yes. If a muscle group (e.g., upper chest, calf) is stagnating, EMS added to traditional training can provide targeted extra fiber activation. Modern literature suggests combined approaches can yield extra strength gains.2, 8 But don’t expect EMS alone to break through stagnation – technique, training volume, recovery, nutrition, and genetics all play roles.
Yes, this is one of the best uses. While you rest the injured joint, the stimulator maintains related and other muscle groups – your combo won’t waste away during the missed weeks. Superimposed NMES after ACL surgery is clinically proven to yield better outcomes than standard rehab.9 For injury-specific protocols consult your physician or physiotherapist.
ActionNOW is a program group in Globus devices built on the superimposed principle: stimulation is applied DURING the active exercise. For bodybuilders this is particularly useful: you don’t separate EMS and weights, you do both together. The brain and muscle train the targeted movement pattern together, producing better adaptation than classical passive EMS according to modern literature.2
Summary – Quick overview
EMS – electrical muscle stimulation (main pillar) ↑
EMS training programs and their application (ActionNOW detailed) ←→
Biohacking with a muscle stimulator ←→
Regaining lost muscle strength (post-injury rehab) ←→
Using muscle stimulation after surgery ←→
Sources
- Happ KA, Behringer M. (2022). Neuromuscular electrical stimulation training vs. conventional strength training: a systematic review and meta-analysis of the effect on strength development. Journal of Strength and Conditioning Research 36(12):3527-3540. PubMed: 34417404
- Micke F, Held S, Lindenthal J, Donath L. (2023). Effects of electromyostimulation on performance parameters in sportive and trained athletes: a systematic review and network meta-analysis. European Journal of Sport Science 23(8):1570-1580. PubMed: 35913269
- Wachi M, Jiroumaru T, Satonaka A, Tanaka K, et al. (2025). Effect of passive warm-up using high-voltage pulsed-current electrical stimulation on jump performance in young adults: a randomized controlled trial. Cureus 17(4):e81594. PubMed: 40322448
- Maffiuletti NA. (2010). Physiological and methodological considerations for the use of neuromuscular electrical stimulation. European Journal of Applied Physiology 110(2):223-234. PubMed: 20473619
- Malone JK, Blake C, Caulfield BM. (2014). Neuromuscular Electrical Stimulation During Recovery From Exercise: A Systematic Review. Journal of Strength and Conditioning Research 28(9):2478-2506. PubMed: 24552796
- Neric FB, Beam WC, Brown LE, Wiersma LD. (2009). Comparison of swim recovery and muscle stimulation on lactate removal after sprint swimming. Journal of Strength and Conditioning Research 23(9):2560-2567. PubMed: 19910818
- Bickel CS, Gregory CM, Dean JC. (2011). Motor unit recruitment during neuromuscular electrical stimulation: a critical appraisal. European Journal of Applied Physiology 111(10):2399-2407. PubMed: 21870119
- Filipovic A, Kleinöder H, Dörmann U, Mester J. (2012). Electromyostimulation — a systematic review of the effects of different electromyostimulation methods on selected strength parameters in trained and elite athletes. Journal of Strength and Conditioning Research 26(9):2600-2614. PubMed: 22067247
- Labanca L, Rocchi JE, Giannini S, Faloni ER, et al. (2022). Early Superimposed NMES Training is Effective to Improve Strength and Function Following ACL Reconstruction with Hamstring Graft regardless of Tendon Regeneration. Journal of Sports Science & Medicine 21(1):91-103. PubMed: 35250338
