Article

Use of a neuromuscular electrical stimulation device for facial muscle toning: A randomized, controlled trial

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Age-related loss of muscle mass contributes to aging of the human face. To evaluate the effects of a neuromuscular electrical stimulation (NMES) device on facial muscle tone and signs of facial aging in healthy women. One hundred and eight healthy women (mean age 43.7, range 32 to 58-45 years) participated in this randomized, controlled, partially blinded study. Participants were randomized to 12 weeks' treatment with the NMES facial device (20 min/day, 5 days/week) or to a nonintervention control group. Participants could not alter fitness, diet or facial care routines during the study. Assessments included psychometric evaluations of facial appearance and assessor-blinded ultrasound measurements of the thickness of the zygomatic major muscle. Mean muscle thickness increased vs. baseline in the NMES group (18.6%) but not the control group. Between-group differences were significant at 6 and 12 weeks (P = 0.05 and P = 0.0001). NMES users reported subjective improvements in facial attributes. The control group did not. In an overall evaluation, ≥80% of NMES users reported improved firmness, tone and lift vs. <5% of the control group (P < 0.001). A 12-week course of facial NMES was associated with increased thickness of the zygomatic major muscle and subjective improvements in facial attributes.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... studies investigating the effects either positive or negative of facial exercises for facial rejuvenation have reported a low level of evidence. 9,11,12 Kim et al. 13 reported that facial exercises increased the cross-sectional area of facial muscles, making the muscles stronger and shorter and the attached skin firmer and more elastic, and that there was a direct relationship between increased facial muscle strength and improved skin elastici-This is an Open Access article distribute under the terms of the Creative Commons Attribution Non-commercial License (https:// creativecommons.org/license/by-nc/4.0.) which permits unrestricted non-commercial use, distribution,and reproduction in any medium, provided the original work is properly cited. ...
... They also reported that facial exercise equipment could lead to subjective improvements of the degree of wrinkles, tone, and complexion. 9,11 However, decreases fat infiltration into the muscles. [14][15][16] Facial muscle mass, in turn, is closely correlated with facial youthfulness. ...
... In one study in this review, 20 weeks of facial exercise therapy was shown to improve midfacial and lower facial fullness, leading to hypertrophy due to exercise of the cheeks and other muscles. 17 In addition, Kim et al. 9,11 reported that facial isometric exercise was effective in improving facial skin elasticity. 13 A previous study reported that facial muscle size increased in response to not only facial exercise, but also neuromuscular electrical stimulation or an oscillatory movement device. ...
... It has been proposed that facial exercising aids in tissue regeneration by increasing circulation to the facial muscles and allowing for drainage of generated waste products [11]. The goal of facial exercising is to combat the multitude of underlying processes that cause wrinkling and skin laxity, including hormone level changes, muscle atrophy, and redistribution of subcutaneous fat [12]. ...
... Facial acupuncture Increase in skin oil content [13] Performed by hand, so can be used more readily on sensitive or narrow areas not amenable to certain instruments [15] Decrease in size of nasolabial folds and eye wrinkles [15] Decrease in overall melasma area and pigment darkness [16] Bruising, edema, pain at needle site [14] Foreign body granuloma [18,19] Atypical mycobacterium infection [20,21] Facial exercises Decrease in self-reported severity of wrinkles and jawline sagging [11] Potential to cause dynamic rhytides [10] Increase in muscle thickness and cross-sectional area [11,12] Increase in physician-rated upper and lower cheek fullness [17] No other adverse events reported in the literature ...
... A total of eight studies were reviewed, four of which involved facial acupuncture and four involving facial exercises [10][11][12][13][14][15][16][17]. The countries represented in the studies involving acupuncture include Korea (n = 2), Thailand (n = 1), and Japan (n = 1). ...
Article
Full-text available
While injectables, lasers, and surgical interventions have traditionally been used to reverse the changes associated with facial aging, other alternative therapies such as facial acupuncture and facial exercises are now being studied for facial rejuvenation. In this paper, we both summarize the concepts of facial acupuncture and facial exercises, and review seven studies that evaluate the efficacy of these modalities. Data from these studies suggest that both facial acupuncture and facial exercises have the potential to improve the skin laxity, wrinkle length, muscle thickness, and pigmentary changes associated with aging. Patients frequently reported improvement and experienced very few side effects. However, further research is necessary before these modalities are widely accepted as effective by the medical community, though the results of these studies may ultimately make providers less hesitant when patients seek out these services.
... Four studies [15][16][17][18] were included in our analysis, totaling 188 adults ( Figure 1 and Table 2). Two of the four studies included compared the experimental group to a control group. ...
... Training conditions varied; neuromuscular electrical stimulation (NMES) was used in two studies, the other two studies used an oscillatory movement device and voluntary facial isometric exercise. Four studies [15][16][17][18] were included in our analysis, totaling 188 adults ( Figure 1 and Table 2). Two of the four studies included compared the experimental group to a control group. ...
... Training conditions varied; neuromuscular electrical stimulation (NMES) was used in two studies, the other two studies used an oscillatory movement device and voluntary facial isometric exercise. Two studies measured facial muscle thickness (MT) and cross-sectional area (CSA) using ultrasonography before and after a 12-week NMES program [15] or 8 weeks of oscillatory movement of a face [18]. The NMES study reported a significant increase in MT of the zygomatic major muscle in the experimental group compared to the control group following the intervention [15]. ...
Article
Full-text available
In this review, we summarize recent literature investigating facial-exercise-induced changes in facial soft tissue. A literature search was performed in PubMed for the terms facial exercise, rejuvenation, muscle, skin, and aging. Four studies were identified from the search and were subject to further assessment. Four studies were included in our analysis. Two of the four studies included compared the experimental (training) group to a control group. The other two studies had no control group. The participants were mainly middle-aged women. Training conditions varied; neuromuscular electrical stimulation (NMES) was used in two studies, the other two studies used an oscillatory movement device and voluntary facial isometric exercise. Two studies measured facial muscle size using ultrasonography before and after 12 weeks of NMES or 8 weeks of oscillatory movement of the face. One study assessed the changes in facial skin elasticity in a single group following 8 weeks of facial isometric exercise, while one study measured strength of labial and lingual muscles before and following 4 weeks of NMES. We found two studies that reported facial-exercise-induced increases in facial muscle size in middle-aged women. It was also reported that facial skin function may improve following facial isometric exercise. Future research is needed to clarify how these changes link with facial rejuvenation. Compared to extremity muscles, the facial muscles are small in size, their shapes are complex, and the boundaries with other tissues may be unclear. Future study is also necessary to examine the reliability of measurements of the facial muscles.
... Further, pain/ discomfort was the stated reason for one in 68 [13] and one in 9 [14] participants to withdraw from an NMES study. Another concern is skin irritation (redness of the skin underneath the surface electrode), which is shortlived fading after 20-30 min [15]. Skin irritation can occur due to excessive 'Joule heating' , namely the buildup of heat due to current resistance in the skin [16,17]. ...
... To date, NMES has rarely been used in the face for scientific purposes, and even less so in healthy participants (although private companies claim that their commercial devices result in "facial toning" [15]. Some studies have applied NMES to the face in clinical populations, for example, to treat facial paralysis [18][19][20], symptoms of depression [21], and assist individuals with dysphasia with swallowing of food [22]. ...
Article
Full-text available
Facial neuromuscular electrical stimulation (NMES) is the application of an electrical current to the skin to induce muscle contractions and has enormous potential for basic research and clinical intervention in psychology and neuroscience. Because the technique remains largely unknown, and the prospect of receiving electricity to the face can be daunting, willingness to receive facial NMES is likely to be low and gender differences might exist in the amount of concern for the sensation of pain and skin burns. We investigated these questions in 182 healthy participants. The likelihood of taking part (LOTP) in a hypothetical facial NMES study was measured both before and after presenting a detailed vignette about facial NMES including its risks. Results showed that LOTP was generally high and that participants remained more likely to participate than not to, despite a decrease in LOTP after the detailed vignette. LOTP was significantly predicted by participants’ previous knowledge about electrical stimulation and their tendency not to worry about the sensations of pain, and it was inversely related to concerns for burns and loss of muscle control. Fear of pain was also inversely related to LOTP, but its effect was mediated by the other concerns. We conclude that willingness to receive facial NMES is generally high across individuals in the studied age range (18–45) and that it is particularly important to reassure participants about facial NMES safety regarding burns and loss of muscle control. The findings are relevant for scholars considering using facial NMES in the laboratory.
... The effect of NMES as a modality has been investigated in (a) patients with obstructive sleep apnea [2][3][4][5][6][7]; (b) within the facial palsy population [8]; (c) facial cosmetics [8], (d) in muscles that are involved in speech articulation [9,10] and (e) swallowing [9][10][11][12][13]. ...
... The effect of NMES as a modality has been investigated in (a) patients with obstructive sleep apnea [2][3][4][5][6][7]; (b) within the facial palsy population [8]; (c) facial cosmetics [8], (d) in muscles that are involved in speech articulation [9,10] and (e) swallowing [9][10][11][12][13]. ...
Article
The primary aim of the current study was to evaluate discomfort levels of facial NMES in healthy volunteers. Eight participants completed the Discomfort Level Scale (DLS) following each motor level facial neuromuscular electrical stimulation (NMES) session. Each participant completed 12 sessions of facial NMES for a total of 96 NMES treatments. Pearson product-moment correlation coefficient demonstrated a significant correlation between the facial NMES intensity level and DLS (p < 0.001). This study demonstrated that the DLS is a useful tool to check for discomfort levels in patients who receive facial NMES. Further, this study provides strong support for the tolerability of facial NMES.
... One example is the Bio-medical Research (BMR) Face device, which is an OTC TENS device designed to target the trigeminal nerve and provide neuromuscular electrical stimulation (NMES) to encourage facial rejuvenation for aesthetic purposes. A recent study examined the safety and efficacy of this device at a peak current intensity of 35 mA when used five days per week for 20 min each day for 12 weeks [47]. There were 56 subjects in the active treatment group and 52 in the sham-control group. ...
... There were 56 subjects in the active treatment group and 52 in the sham-control group. There were no significant adverse events in this study, and the only reported side effects were minor skin redness following stimulation, which disappeared within 10e20 min following use [47]. Additionally, there was one report of a subject who experienced eye fluttering, which was thought to be a result of stimulation, although this effect abated after a couple of days. ...
Article
We present device standards for low-power non-invasive electrical brain stimulation devices classified as limited output transcranial electrical stimulation (tES). Emerging applications of limited output tES to modulate brain function span techniques to stimulate brain or nerve structures, including transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), and transcranial pulsed current stimulation (tPCS), have engendered discussion on how access to technology should be regulated. In regards to legal regulations and manufacturing standards for comparable technologies, a comprehensive framework already exists, including quality systems (QS), risk management, and (inter)national electrotechnical standards (IEC). In Part 1, relevant statutes are described for medical and wellness application. While agencies overseeing medical devices have broad jurisdiction, enforcement typically focuses on those devices with medical claims or posing significant risk. Consumer protections regarding responsible marketing and manufacture apply regardless. In Part 2 of this paper, we classify the electrical output performance of devices cleared by the United States Food and Drug Administration (FDA) including over-the-counter (OTC) and prescription electrostimulation devices, devices available for therapeutic or cosmetic purposes, and devices indicated for stimulation of the body or head. Examples include iontophoresis devices, powered muscle stimulators (PMS), cranial electrotherapy stimulation (CES), and transcutaneous electrical nerve stimulation (TENS) devices. Spanning over 13 FDA product codes, more than 1200 electrical stimulators have been cleared for marketing since 1977. The output characteristics of conventional tDCS, tACS, and tPCS techniques are well below those of most FDA cleared devices, including devices that are available OTC and those intended for stimulation on the head. This engineering analysis demonstrates that with regard to output performance and standing regulation, the availability of tDCS, tACS, or tPCS to the public would not introduce risk, provided such devices are responsibly manufactured and legally marketed. In Part 3, we develop voluntary manufacturer guidance for limited output tES that is aligned with current regulatory standards. Based on established medical engineering and scientific principles, we outline a robust and transparent technical framework for ensuring limited output tES devices are designed to minimize risks, while also supporting access and innovation. Alongside applicable medical and government activities, this voluntary industry standard (LOTES-2017) further serves an important role in supporting informed decisions by the public.
... Pleasonton (1970) used electrical stimuli (delivered short electrical pulses) to investigate patterns of sensitivity to contrast the tip and dorsum, midline and lateral areas, and right and left sides of the tongue using electrodes that were placed on the tongue. Daly et al. (1996) motor recovery in SCI, CVA, or TBI after the use of motor prostheses Gibson et al. (1988) Snyder-Mackler et al. (1995 preservation of muscle mass and function during prolonged periods of disuse or immobilization Caggiano et al. (1994) improving of muscle function in healthy elderly subjects Babault et al. (2007) Delitto et al. (1989) Maffiuletti et al. (2002a) Pichon et al. (1995 strengthening skeletal muscles in recreational and competitive athletes Oliven et al. (2009) Hu et al. (2008) Steier et al. (2011) Oliven, Schnall, Pillar, Gavriely, and Odeh (2001 maintaining open airway in patients with obstructive sleep apnea Kavanagh et al. (2012) facial NMES to improve zygomatic major thickness. Most of the studies found in the literature related to lingual electrical stimulation investigated its effect on sleep apnea. ...
... However, few studies to date have investigated the effect of NMES on facial muscles, generally, and muscles of speech production and swallowing, specifically. In a study that targeted the zygomatic major muscle, Kavanagh et al. (2012) concluded that following a 12-week course of facial NMES, the thickness of the muscle was increased as measured by ultrasound and there were subjective improvements in facial characteristics. ...
Article
BACKGROUND: Lingual, labial and buccal weakness (LLBW) is a widespread consequence of several neurological insults. LLBW impact on oral motor functions such as speech production and swallowing is well documented in the literature. Therefore, it is important for the speech-language pathologists to have access to evidence-based approaches for treatment. Thus, it is imperative that the speech-language pathology field search for effective treatment approaches and explore new treatment modalities that can improve therapy outcomes. One relatively new modality in this field is neuromuscular electrical stimulation (NMES).
... The physiologic age-dependent process of loosing mass and proper function of muscles is called sarcopenia. 59,60 The facial muscles, in specific, lengthen with age, increase in muscle tone, and have a shorter amplitude of movement, and the muscle tone at rest is closer to maximum contracture tone. 61 The clinical effect of these changes might be a general tightening of the muscles of the face, with a limited amplitude of facial expression, permanent contractures which result in a potential shifting of fat and thus an accentuation of skin creases, and permanent skin wrinkling with a transformation of dynamic facial lines to static facial lines (►Fig. ...
... 62 Recent studies trying to restore muscle function with facial muscle exercises, however, revealed limited efficacy, 63 whereas the use of neuromuscular electrical stimula-tion reported promising results. 60 However, the observed clinical changes could be due to changes of altered muscle physiology itself or secondary to age-related changes of facial bones and ligaments. As the latter is considered as the more appropriate approach, procedures for facial rejuvenation should integrate all facial tissue into consideration for natural results. ...
Article
Rejuvenative procedures of the face are increasing in numbers, and a plethora of different therapeutic options are available today. Every procedure should aim for the patient's safety first and then for natural and long-lasting results. The face is one of the most complex regions in the human body and research continuously reveals new insights into the complex interplay of the different participating structures. Bone, ligaments, muscles, fat, and skin are the key players in the layered arrangement of the face.Aging occurs in all involved facial structures but the onset and the speed of age-related changes differ between each specific structure, between each individual, and between different ethnic groups. Therefore, knowledge of age-related anatomy is crucial for a physician's work when trying to restore a youthful face.This review focuses on the current understanding of the anatomy of the human face and tries to elucidate the morphological changes during aging of bone, ligaments, muscles, and fat, and their role in rejuvenative procedures. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
... This technique is used in health as skin-functional and aesthetic physiotherapy or rehabilitation and consists of surface electrostimulation for muscle strengthening [19]. Some evidence suggests that neuromuscular electric stimulation such as the Russian current can enable increased facial muscle tone, leading to an increase in muscle activity and enabling better expression and face contour [21,22]. This feature can also prevent the physiological hypotonia caused by biological changes that occur as we get older [23] or in the presence of degenerative diseases in different experimental populations, such as patients with neurological problems [24]. ...
Article
Full-text available
Evidence has supported the use of leucine as a promising agent for the maintenance of muscle tone. This study aimed to assess the combined effect of leucine and cream-based lactic acid (novel cosmetic product), associated with the use of surface electrical stimulation to improve contour and facial tonus in women. A total of 23 women were randomly allocated into two groups: Experimental (EG)—use of the leucine-based cream and lactic acid + electrostimulation for facial toning (mean intensity 13 Hz and protocol in progression); and placebo (GP)—use of the placebo cream (without the addition of leucine and lactic acid) + stimulation with the same protocol as the EG. Each group used their cream daily and underwent the intervention protocol three x/week with stimulation for 40 min, for a total of 8 weeks. Three main outcomes were reported: angular variation of facial contour by means of photogrammetry, muscle tone through the electromyographic activity of the masseter and zygomatic muscles during rest and functional tasks of biting and smiling. A significant effect of the intervention and between the groups was obtained for the experimental group against the placebo group for facial contour and muscle tone. An increased muscular activity of the masseter (average 28%) when smiling, and a reduction of zygomatic activity (in average 41%) when biting were found. The use of cream containing leucine and lactic acid combined with electrostimulation contributes to the improvement of facial contour and muscle tone when biting and smiling.
... It is, however, worth noting that two trials have recorded statistically significant increases in the volume of facial muscles (measured by ultrasound scanning) over an 8-week and 12-week period of FMED use, respectively. 4,5 What is not made clear is whether this represented muscular hypertrophy or indeed contributed to improved facial appearance. The jawline has been a long-standing tenet of beauty standards and many of the FMED on the market claim to improve the appearance of the user's jawline. ...
... In the present study, the relative minimal difference values were over 20% of the mean values for five of the six muscles. When investigating the effect of exercise on facial muscle size, one study demonstrated changes across time relative to a time-matched control group [15]. However, not all studies included this control group. ...
Article
Full-text available
The absolute reliability (i.e., standard error of measurement and minimal difference) of a measurement is important to consider when assessing training effects. However, the absolute reliability for ultrasound measured facial muscle thickness had not been investigated. In order to examine the absolute and relative reliability of measuring facial muscles, 98 healthy, young, and middle-aged adults (18–40 years) had ultrasound measurements taken twice, separated by an average of three days. Six facial muscles were selected to determine the reliability of facial muscle thickness. The relative reliability (ICC3,1) ranged from 0.425 for the orbicularis oris (inferior) to 0.943 for the frontalis muscle. The absolute reliability (minimal difference) ranged from 0.25 mm for the orbicularis oculi to 1.82 mm for the masseter. The percentage minimal difference was 22%, 25%, 26%, 29%, 21%, and 10% for the frontalis, orbicularis oculi, orbicularis oris (superior), orbicularis oris (inferior), depressor anguli oris, and masseter, respectively. Our results indicated that the relative reliability was similar to that observed previously. The absolute reliability indicated that the measurement error associated with measuring muscle thickness of the face may be greater than that of the trunk/limb muscles. This may be related to the difficulty of accurately determining the borders of each muscle.
... However, few studies to date have investigated the effects of NMES on facial muscles, in general, and muscles of speech production and swallowing specifically. In a study that targeted the zygomatic major muscle, Kavanagh et al. (2012) concluded that following a 12-week course of facial NMES, the thickness of the muscle was increased as measured by ultrasound and there were subjective improvements in facial characteristics. ...
Article
Results: On comparing the total change in labial and lingual strength between the two groups, an increase in total labial strength was found in the treatment group compared with the control group. However, the control group showed an increase in total lingual strength compared with the treatment group. Results for all measurements were not statistically significant. This study concluded that NMES may be a promising modality to combine with labial and buccal exercises for improvement of muscle strength.
... A recent study examined the safety and efficacy of this device at a peak current intensity of 35 mA when used five days per week for 20 minutes each day for 12 weeks 67 . There were no significant adverse events in this study and the only reported side effects were minor skin redness following stimulation, which disappeared with 10-20 minutes following use 67 . Consistent with these results, on an acute level we found that TEN did not elicit any significant side effects (Table 2). ...
Article
Full-text available
We engineered a transdermal neuromodulation approach that targets peripheral (cranial and spinal) nerves and utilizes their afferent pathways as signaling conduits to influence brain function. We investigated the effects of this transdermal electrical neurosignaling (TEN) method on sympathetic physiology under different experimental conditions. The TEN method involved delivering high-frequency pulsed electrical currents to ophthalmic and maxillary divisions of the right trigeminal nerve and cervical spinal nerve afferents. Under resting conditions, TEN significantly suppressed basal sympathetic tone compared to sham as indicated by functional infrared thermography of facial temperatures. In a different experiment, subjects treated with TEN reported significantly lower levels of tension and anxiety on the Profile of Mood States scale compared to sham. In a third experiment when subjects were experimentally stressed TEN produced a significant suppression of heart rate variability, galvanic skin conductance, and salivary α-amylase levels compared to sham. Collectively these observations demonstrate TEN can dampen basal sympathetic tone and attenuate sympathetic activity in response to acute stress induction. Our physiological and biochemical observations are consistent with the hypothesis that TEN modulates noradrenergic signaling to suppress sympathetic activity. We conclude that dampening sympathetic activity in such a manner represents a promising approach to managing daily stress.
Article
Purpose Neuromuscular Electrical Stimulation (NMES) is a widely used treatment modality for dysphagia therapy despite the inconclusive evidence of its effectiveness. Our objective was to complete a retrospective review to analyze the results of NMES with our patient population in an acute rehabilitation facility. In this clinical focus article, we briefly review the current literature on NMES, discuss a clinical protocol of NMES use in an inpatient rehabilitation hospital, and discuss the need for future research in this area. Conclusions As with much of the NMES literature, we observed improvement in the ability to swallow following a cerebrovascular accident and traumatic brain injury when a combination of swallowing therapy and NMES treatment was used. Although this combination works for our patients to improve swallow function, the impact of swallow therapy alone remains unclear. Further investigative research to clarify NMES protocols and patient population is needed to optimize results. Therefore, a large randomized clinical trial would be beneficial to clearly define the role of NMES in recovery of swallowing ability following a brain injury.
Article
Introduction: Powered muscle stimulators have been popularized in recent years due to their muscle toning effects. This study aims to describe marketing trends and reporting of adverse effects of powered muscle stimulators. Methods: We performed a cross-sectional retrospective analysis of records from the United States FDA database for 510(k) premarket approval of powered muscle stimulators between January 1, 2000 and December 31, 2018. The FDA MAUDE database was reviewed for adverse events reported with device usage. Results: One hundred and seventeen devices received 510(k) premarket approval between 2000 and 2018, with the first approval occurring in 2001. Initially, devices were marketed to assist with muscle toning and strengthening, but more recent indications include the treatment of pain, increased local muscle blood circulation, and prevention of post-surgical venous thrombosis. Thirty-six adverse event reports have been submitted and published in the MAUDE database over the past 10 years by 11% of manufacturers. Discussion: Powered muscle stimulators are growing increasingly popular amongst consumers and healthcare providers due to their ease of use and perceived aesthetic, muscle strength, and pain relief benefits. Additional investigation to determine optimal treatment parameters and potential adverse effects is necessary due to the growing popularity of these devices.
Article
Full-text available
Objective: This study explored the effect of facial and submental neuromuscular electrical stimulation (NMES) in individuals with lingual, labial and buccal weakness. Method: An ABC/ACB design was used. Two male participants who acquired cerebrovascular accident (60 years) involved in this study. Both engaged in 2 treatment phases. One phase included performing an oral motor exercise program in conjunction with the NMES. Second phase included performing only oral motor exercise program. Results: Submental NMES did not have any effect on lingual strength. However, facial NMES had positive effect on labial strength in the 2 participants.
Article
Full-text available
Effects of strength training (ST) for 21 wk were examined in 10 older women (64 ± 3 yr). Electromyogram, maximal isometric force, one-repetition maximum strength, and rate of force development of the leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris (QF) and of vastus lateralis (VL), medialis (VM), intermedius (VI) and rectus femoris (RF) throughout the lengths of 3/12–12/15 (Lf) of the femur, muscle fiber proportion and areas of types I, IIa, and IIb of the VL were evaluated. Serum hormone concentrations of testosterone, growth hormone (GH), cortisol, and IGF-I were analyzed for the resting, preexercise, and postexercise conditions. After the 21-wk ST, maximal force increased by 37% ( P < 0.001) and 1-RM by 29% ( P < 0.001), accompanied by an increase ( P < 0.01) in rate of force development. The integrated electromyograms of the vastus muscles increased ( P < 0.05). The CSA of the total QF increased ( P < 0.05) throughout the length of the femur by 5–9%. The increases were significant ( P< 0.05) at 7/15–12/15 Lf for VL and at 3/15–8/15 Lf for VM, at 5/15–9/15 for VI and at 9/15 ( P < 0.05) for RF. The fiber areas of type I ( P < 0.05), IIa ( P < 0.001), and IIb ( P < 0.001) increased by 22–36%. No changes occurred during ST in serum basal concentrations of the hormones examined, but the level of testosterone correlated with the changes in the CSA of the QF ( r = 0.64, P < 0.05). An acute increase of GH ( P < 0.05), remaining elevated up to 30 min ( P < 0.05) postloading, was observed only at posttraining. Both neural adaptations and the capacity of skeletal muscle to undergo training-induced hypertrophy even in older women explain the strength gains. The increases in the CSA of the QF occurred throughout its length but differed selectively between the individual muscles. The serum concentrations of hormones remained unaltered, but a low level of testosterone may be a limiting factor in training-induced muscle hypertrophy. The magnitude and time duration of the acute GH response may be important physiological indicators of anabolic adaptations during strength training even in older women.
Article
Full-text available
We studied the effects of self-administered neuromuscular electrical stimulation (NMES) on changes in strength, endurance, selected anthropometric measures, and subject's perceived shape and satisfaction of the abdominal wall. Twenty-four adults (experimental group) stimulated their abdominals 5 days per week (20-40 minutes per session) for 8 weeks and refrained from engaging in any additional exercise during the study. A control group (N=16) refrained from exercising the abdominals or engaging in any other exercise training during the study. Subjects were tested at the beginning, mid-point, and end of the study. Isometric strength of the abdominal muscles was tested using a isokinetic dynamometer, endurance was measured using the ACSM curl-up test, abdominal circumference was measured using a steel tape measure, and body shape and satisfaction were assessed via questionnaire. The stimulation group had a 58% increase in abdominal strength, whereas the control group did not change. The stimulation group also had a 100% increase in abdominal endurance versus a 28% increase in the control group. Waist circumference decreased by of 3.5 cm in the stimulation group compared to no significant change in the control group. All 24 subjects in the stimulation group felt that their midsections were more "toned" and "firmed" and 13/24 (54%) felt that their posture had improved as a result of the stimulation. None of the control group subjects reported changes in these parameters. There were no significant differences in body weight, BMI, or skinfold thickness over the course of the study in either group. NMES, as used in the current study, resulted in significant improvements in the muscular strength and endurance of the abdominal region, as well as subject's perceived shape and satisfaction of the mid-section.
Article
Full-text available
The aging process is associated with loss of muscle mass and strength and decline in physical functioning. The term sarcopenia is primarily defined as low level of muscle mass resulting from age-related muscle loss, but its definition is often broadened to include the underlying cellular processes involved in skeletal muscle loss as well as their clinical manifestations. The underlying cellular changes involve weakening of factors promoting muscle anabolism and increased expression of inflammatory factors and other agents which contribute to skeletal muscle catabolism. At the cellular level, these molecular processes are manifested in a loss of muscle fiber cross-sectional area, loss of innervation, and adaptive changes in the proportions of slow and fast motor units in muscle tissue. Ultimately, these alterations translate to bulk changes in muscle mass, strength, and function which lead to reduced physical performance, disability, increased risk of fall-related injury, and, often, frailty. In this review, we summarize current understanding of the mechanisms underlying sarcopenia and age-related changes in muscle tissue morphology and function. We also discuss the resulting long-term outcomes in terms of loss of function, which causes increased risk of musculoskeletal injuries and other morbidities, leading to frailty and loss of independence.
Article
Full-text available
The effects of strength conditioning on skeletal muscle function and mass were determined in older men. Twelve healthy untrained volunteers (age range 60-72 yr) participated in a 12-wk strength training program (8 repetitions/set; 3 sets/day; 3 days/wk) at 80% of the one repetition maximum (1 RM) for extensors and flexors of both knee joints. They were evaluated before the program and after 6 and 12 wk of training. Weekly measurements of 1 RM showed a progressive increase in strength in extensors and flexors. By 12 wk extensor and flexor strength had increased 107.4 (P less than 0.0001) and 226.7% (P less than 0.0001), respectively. Isokinetic peak torque of extensors and flexors measured on a Cybex II dynamometer increased 10.0 and 18.5% (P less than 0.05) at 60 degrees/s and 16.7 and 14.7% (P less than 0.05) at 240 degrees/s. The torque-velocity relationship showed an upward displacement of the curve at the end of training, mainly in the slow-velocity high-torque region. Midthigh composition from computerized tomographic scans showed an increase (P less than 0.01) in total thigh area (4.8%), total muscle area (11.4%), and quadriceps area (9.3%). Biopsies of the vastus lateralis muscle revealed similar increases (P less than 0.001) in type I fiber area (33.5%) and type II fiber area (27.6%). Daily excretion of urinary 3-methyl-L-histidine increased with training (P less than 0.05) by an average 40.8%. Strength gains in older men were associated with significant muscle hypertrophy and an increase in myofibrillar protein turnover.
Article
Full-text available
Sarcopenia, the loss of muscle mass and strength with age, is becoming recognized as a major cause of disability and morbidity in the elderly population. Sarcopenia is part of normal aging and does not require a disease to occur, although muscle wasting is accelerated by chronic diseases. Sarcopenia is thought to have multiple causes, although the relative importance of each is not clear. Neurological, metabolic, hormonal, nutritional, and physical-activity–related changes with age are likely to contribute to the loss of muscle mass. In this review, we discuss current concepts of the pathogenesis, treatment, and prevention of sarcopenia.
Article
Full-text available
Effects of strength training (ST) for 21 wk were examined in 10 older women (64 +/- 3 yr). Electromyogram, maximal isometric force, one-repetition maximum strength, and rate of force development of the leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris (QF) and of vastus lateralis (VL), medialis (VM), intermedius (VI) and rectus femoris (RF) throughout the lengths of 3/12--12/15 (Lf) of the femur, muscle fiber proportion and areas of types I, IIa, and IIb of the VL were evaluated. Serum hormone concentrations of testosterone, growth hormone (GH), cortisol, and IGF-I were analyzed for the resting, preexercise, and postexercise conditions. After the 21-wk ST, maximal force increased by 37% (P < 0.001) and 1-RM by 29% (P < 0.001), accompanied by an increase (P < 0.01) in rate of force development. The integrated electromyograms of the vastus muscles increased (P < 0.05). The CSA of the total QF increased (P < 0.05) throughout the length of the femur by 5--9%. The increases were significant (P < 0.05) at 7/15--12/15 Lf for VL and at 3/15--8/15 Lf for VM, at 5/15--9/15 for VI and at 9/15 (P < 0.05) for RF. The fiber areas of type I (P < 0.05), IIa (P < 0.001), and IIb (P < 0.001) increased by 22--36%. No changes occurred during ST in serum basal concentrations of the hormones examined, but the level of testosterone correlated with the changes in the CSA of the QF (r = 0.64, P < 0.05). An acute increase of GH (P < 0.05), remaining elevated up to 30 min (P < 0.05) postloading, was observed only at posttraining. Both neural adaptations and the capacity of skeletal muscle to undergo training-induced hypertrophy even in older women explain the strength gains. The increases in the CSA of the QF occurred throughout its length but differed selectively between the individual muscles. The serum concentrations of hormones remained unaltered, but a low level of testosterone may be a limiting factor in training-induced muscle hypertrophy. The magnitude and time duration of the acute GH response may be important physiological indicators of anabolic adaptations during strength training even in older women.
Article
Full-text available
Devices for neuromuscular electrical stimulation (NMES) are increasingly used by individuals without specific injuries and are standard equipment in most physical therapy practices. The most often stimulated muscle group is the quadriceps femoris. We designed a systematic review and meta-analysis of randomised controlled trials to determine whether NMES is an effective modality for strength augmentation of the quadriceps femoris. A full content search for randomised controlled trials was performed in Medline, Embase, Cinahl, the Cochrane Controlled Trials Register and the Physical Therapy Evidence Database. Maximum volitional isometric or isokinetic muscle torque in Nm was used as main outcome measure. Thirty-five trials were included and evaluated. A fundamental distinction was made between the trials using subjects with unimpaired quadriceps femoris muscles and the trials using post-injury or post-operative subjects. In the unimpaired quadriceps subgroup, meta-analyses were performed for the comparisons ‘NMES versus no exercises’ and ‘NMES versus volitional exercises’. All other comparisons were evaluated descriptively. The included trials were generally of poor quality and meta-analytic data indicate that publication bias may be present. The evaluated data suggest that, both for the unimpaired and impaired quadriceps, NMES makes sense compared with doing no exercises but volitional exercises appear to be more effective in most situations. Based on the available evidence, NMES may only be preferred over volitional training for within-cast muscle training and perhaps in specific situations where volitional training does not receive sufficient patient compliance. Further research should be directed toward identifying the clinical impact at activity and participation levels and the optimal stimulation parameters of this modality.
Article
We conducted a 12-wk resistance training program in elderly women [mean age 69 +/- 1.0 (SE) yr] to determine whether increases in muscle strength are associated with changes in cross-sectional fiber area of the vastus lateralis muscle. Twenty-seven healthy women were randomly assigned to either a control or exercise group. The program was satisfactorily completed and adequate biopsy material obtained from 6 controls and 13 exercisers. After initial testing of baseline maximal strength, exercisers began a training regimen consisting of seven exercises that stressed primary muscle groups of the lower extremities. No active intervention was prescribed for the controls. Increases in muscle strength of the exercising subjects were significant compared with baseline values (28-115%) in all muscle groups. No significant strength changes were observed in the controls. Cross-sectional area of type II muscle fibers significantly increased in the exercisers (20.1 +/- 6.8%, P = 0.02) compared with baseline. In contrast, no significant change in type II fiber area was observed in the controls. No significant changes in type I fiber area were found in either group. We conclude that a program of resistance exercise can be safely carried out by elderly women, such a program significantly increases muscle strength, and such gains are due, at least in part, to muscle hypertrophy.
Article
Facial aging reflects the dynamic, cumulative effects of time on the skin, soft tissues, and deep structural components of the face, and is a complex synergy of skin textural changes and loss of facial volume. Many of the facial manifestations of aging reflect the combined effects of gravity, progressive bone resorption, decreased tissue elasticity, and redistribution of subcutaneous fullness. A convenient method for assessing the morphological effects of aging is to divide the face into the upper third (forehead and brows), middle third (midface and nose), and lower third (chin, jawline, and neck). The midface is an important factor in facial aesthetics because perceptions of facial attractiveness are largely founded on the synergy of the eyes, nose, lips, and cheek bones (central facial triangle). For aesthetic purposes, this area should be considered from a 3-dimensional rather than a 2-dimensional perspective, and restoration of a youthful 3-dimensional facial topography should be regarded as the primary goal in facial rejuvenation. Recent years have seen a significant increase in the number of nonsurgical procedures performed for facial rejuvenation. Patients seeking alternatives to surgical procedures include those who require restoration of lost facial volume, those who wish to enhance normal facial features, and those who want to correct facial asymmetry. Important factors in selecting a nonsurgical treatment option include the advantages of an immediate cosmetic result and a short recovery time.
Article
Neuromuscular electrical stimulation (NMES) has been in practice since the eighteenth century for the treatment of paralysed patients and the prevention and/or restoration of muscle function after injuries, before patients are capable of voluntary exercise training. More recently NMES has been used as a modality of strengthening in healthy subjects and highly trained athletes, but it is not clear whether NMES is a substitute for, or a complement to, voluntary exercise training. Moreover the discussion of the mechanisms which underly the specific effects of NMES appears rather complex at least in part because of the disparity in training protocols, electrical stimulation regimens and testing procedures that are used in the various studies. It appears from this review of the literature that in physical therapy, NMES effectively retards muscle wasting during denervation or immobilisation and optimises recovery of muscle strength during rehabilitation. It is also effective in athletes with injured, painful limbs, since NMES contributes to a shortened rehabilitation time and aids a safe return to competition. In healthy muscles, NMES appears to be a complement to voluntary training because it specifically induces the activity of large motor units which are more difficult to activate during voluntary contraction. However, there is a consensus that the force increases induced by NMES are similar to, but not greater than, those induced by voluntary training. The rationale for the complementarity between NMES and voluntary exercise is that in voluntary contractions motor units are recruited in order, from smaller fatigue resistant (type I) units to larger quickly fatiguable (type II) units, whereas in NMES the sequence appears to be reversed. As a training modality NMES is, in nonextreme situations such as muscle denervation, not a substitute for, but a complement of, voluntary exercise of disused and healthy muscles.
Article
We conducted a 12-wk resistance training program in elderly women [mean age 69 +/- 1.0 (SE) yr] to determine whether increases in muscle strength are associated with changes in cross-sectional fiber area of the vastus lateralis muscle. Twenty-seven healthy women were randomly assigned to either a control or exercise group. The program was satisfactorily completed and adequate biopsy material obtained from 6 controls and 13 exercisers. After initial testing of baseline maximal strength, exercisers began a training regimen consisting of seven exercises that stressed primary muscle groups of the lower extremities. No active intervention was prescribed for the controls. Increases in muscle strength of the exercising subjects were significant compared with baseline values (28-115%) in all muscle groups. No significant strength changes were observed in the controls. Cross-sectional area of type II muscle fibers significantly increased in the exercisers (20.1 +/- 6.8%, P = 0.02) compared with baseline. In contrast, no significant change in type II fiber area was observed in the controls. No significant changes in type I fiber area were found in either group. We conclude that a program of resistance exercise can be safely carried out by elderly women, such a program significantly increases muscle strength, and such gains are due, at least in part, to muscle hypertrophy.
Article
To determine the impact of an 8-wk neuromuscular stimulation program of thigh muscles on strength and cross-sectional area in patients with refractory heart failure listed for transplantation. Forty-two patients with a stable disease course were assigned randomly to a stimulation group (SG) or a control group (CG). The stimulation protocol consisted of biphasic symmetric impulses with a frequency of 50 Hz and an on/off regime of 2/6 sec. Primary outcome measures were isometric and isokinetic thigh muscle strength and muscle cross-sectional area. Our results showed an increase of muscle strength by mean 22.7 for knee extensor and by 35.4 for knee flexor muscles. The CG remained unchanged or decreased by -8.4 in extensor strength. Cross-sectional area increased in the SG by 15.5 and in the CG by 1.7. Activities of daily living as well as quality of life increased in the SG but not in the CG. Subscales of the SF-36 increased significantly in the SG, especially concerning physical functioning by +7.5 (1.3-30.0), emotional role by +33.3 (0-66.6), and social functioning by +18.8 (0-46.9), all P < 0.05. Neither a change nor a decrease was observed in the CG. Neuromuscular electrical stimulation of thigh muscles in patients with refractory heart failure is effective in increasing muscle strength and bulk and positively affects the perception of quality of life and activities of daily living.
Article
The major forces responsible for facial aging include gravity, soft tissue maturation, skeletal remodeling, muscular facial activity, and solar changes. This article discusses the anatomy and pathophysiology of facial aging by defining the affects of the aging process on the skeletal structure, skin, and musculature. How these changes affect the upper, mid, and lower thirds of the aging face is then examined.
Article
This study assessed age and sex effects on muscle fibre adaptations to heavy-resistance strength training (ST). Twenty-two young men and women (20-30 years old) and 18 older men and women (65-75 years old) completed 9 weeks of heavy-resistance knee extension exercises with the dominant leg 3 days week(-1); the non-dominant leg served as a within-subject, untrained control. Bilateral vastus lateralis muscle biopsies were obtained before and after ST for analysis of type I, IIa and IIx muscle fibre cross-sectional area (CSA) and fibre type distribution. One-repetition maximum (1-RM) strength was also assessed before and after ST. ST resulted in increased CSA of type I, IIa and IIx muscle fibres in the trained leg of young men, type I and IIa fibres in young women, type IIa fibres in older men, and type IIx fibres in older women (all P<0.05). Analysis of fibre type distribution revealed a significant increase in the percentage of type I fibres (P<0.05) along with a decrease in type IIx fibres (P=0.054) after ST only in young women. There were no significant changes in muscle fibre CSA or fibre type distribution in the untrained leg for any group. All groups displayed significant increases in 1-RM (27-39%; all P<0.01). In summary, ST led to significant increases in 1-RM and type II fibre CSA in all groups; however, age and sex influence specific muscle fibre subtype responses to ST.
Does neuromuscular electrical stimulation strengthen the quadriceps femoris? A systematic review of randomised controlled trials
  • Bax