The present study aimed to evaluate the effects of two types of 9-month adapted physical activity (APA) program, based on a muscle reinforcement training and a postural training, respectively, on muscle mass, muscle strength, and static balance in moderate sarcopenic older women. The diagnosis of sarcopenia was done in accordance with measurable variables and cut-off points suggested by the European Working Group on Sarcopenia in Older People (EWGSOP). Seventy-two participants were randomly assigned to two groups: the muscle reinforcement training group (RESISTANCE) (n=35; 69.9 ± 2.7 years) and the postural training group (POSTURAL) (n=37; 70.0±2.8 years). Body composition, muscle mass, skeletal muscle mass index (SMI), and handgrip strength (HGS) were evaluated for sarcopenia assessment, whereas Sway Path, Sway Area, Stay Time, and Spatial Distance were evaluated for static balance assessment. Sixty-six participants completed the study (RESISTANCE group: n=33; POSTURAL group: n=33). Significant increases of muscle mass, SMI, and handgrip strength values were found in the RESISTANCE group, after muscle reinforcement program. No significant differences appeared in the POSTURAL group, after postural training. Furthermore, RESISTANCE group showed significant improvements in static balance parameters, whereas no significant differences appeared in the POSTURAL group. On the whole, the results of this study suggest that the APA program based on muscle reinforcement applied on moderate sarcopenic older women was able to significantly improve muscle mass and muscle strength, and it was also more effective than the applied postural protocol in determining positive effects on static balance.
The older population in the world is predicted to increase by threefold within 50 years, from 600 million people in 2000 to over two billion in 2050. This increase may be viewed as one of society’s greatest achievements, but preserving older adults’ independence and quality of life remains one of the major clinical and public health challenges [
The impaired state of health induced by sarcopenia is closely related to a risk of adverse outcomes such as physical disability, poor quality of life, impaired ability to perform activities of daily living [
Exercise has been shown to reduce the incidence of falls by 13% to 40%, which has led to a broad consensus among experts that older adults should be offered exercises that incorporate elements of balance and strength training [
Initially, 82 potential participants were assessed for eligibility from the community through advertisements in the notice board of the Public Health Service ASL 4 Chiavari, Italy, and in the local newspaper and the screening period was conducted between August and September 2016.
The recruitment process consisted of a medical evaluation to assess their good health and the absence of any contraindication to participation in adapted physical activity programs.
Participants were required to be at least 65 years of age and they were excluded if they had a pacemaker (due to the use of bioelectrical impedance analysis) or previous health problems such as neurological or cardiovascular diseases that would limit participation in the APA programs.
During enrolment, 10 potential participants were excluded, because 6 did not meet inclusion criteria and the other 4 declined to participate.
At the end of the recruitment, 72 participants were enrolled for the study and they were randomly divided into two groups assigned to one of the two APA programs: muscle reinforcement training group (RESISTANCE) (n=35) and postural training group (POSTURAL) (n=37). Two out of 35 participants of the RESISTANCE group and 4 out of 37 participants of the POSTURAL group did not complete the training programs. A flow diagram of the study is reported in Figure
Flow diagram of the study.
The participant characteristics of the two groups at baseline are reported in Table
Participant characteristics at baseline. Data are means ± SD.
RESISTANCE (n=35) | POSTURAL (n=37) | p-value | |
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Age (years) | 69.9±2.7 | 70.0±2.8 | n.s. |
Height (cm) | 1.62±0.02 | 1.59±0.01 | n.s. |
Body mass (kg) | 63.86±1.75 | 63.77±2.15 | n.s. |
Body mass index (kg/m2) | 24.34±0.72 | 25.23±0.86 | n.s. |
Handgrip strength (kg) (mean of the two sides) | 17.84±4.97 | 17.86±5.3 | n.s. |
The experimental protocol was approved by the Ethics Committee of the University of Genoa and, after explaining the aim and the procedure of the study, all participants gave their informed consent for intervention.
Estimation of sample size for this investigation was performed using handgrip strength as one of our primary outcome measures. Sample size was estimated combining the normative data and the genuine change in grip strength determined in previous works [
Testing was conducted before (T0) and after (T1) the APA intervention.
Before starting the APA program, all the participants were asked to answer to a food questionnaire in order to check a balanced daily intake of nutrients.
Body mass and height were measured to the nearest 0.1 kg and 0.5 cm, respectively, using a mechanical column scale and a stadiometer. Body composition evaluation was performed using a bioimpedance scale (InBody 320, GBC BioMed, NZ) at least 2 hours after the meal and participants were required to wear light clothing with bare feet. After ensuring proper feet placement and hold of hand electrodes, participants were instructed to stay relaxed during the measurements, maintaining a normal standing position, with arms and legs extended. The parameters used to measure the body composition were weight (Kg), body mass index (BMI), and muscle mass (Kg).
The skeletal muscle mass (SM) was calculated with the regression equation (
The same authors defined SM index (SMI) considering SMI as SM (Kg), obtained from the above-mentioned prediction equation, adjusted for the squared height (SM/height2, Kg/m2).
Sarcopenia was diagnosed in accordance with EWGSOP criteria [
All participants performed the balance assessment on a static force platform (ARGO, RGM Medical Devices S.p.A., Genoa, Italy). The ARGO static force platform has a large platform surface area (600 x 600 mm) and a high sampling frequency (100 Hz). This platform, even with short measurement times, allows a reliable harmonic analysis of sway density parameters [
Participants were asked to stand with their feet joined and parallel on the barefoot, with their arms hanging loose at sides, and with closed mouth and unclenched teeth, looking at a target placed at their eye level about 1 m in front of them, in an acoustically isolated room and darkened when they were in closed eyes (CE) condition. Participants executed two trials in two different randomized modalities: with open eyes (OE) and with closed eyes (CE). Each assessment lasted 40 seconds preceded by a 5-second waiting time that allowed the participants to become familiar with the position, thus reducing the adaptation artifact [
(1) Sway Path (SP) (mm/s), defined as Length of the Sway Path, normalized with respect to the duration of the acquisition interval;
(2) Sway Area (SA) (mm2/s), defined as the Sway Area by the radius connecting each subsequent point of the statokinesigram to the average position of the Centre of Pressure (COP), normalized with respect to the duration of the acquisition interval;
(3) Stay Time (ST) (s), the mean Stay Time spent by the COP trace in the neighbourhood of each peak, over the observed sway of each subject;
(4) Spatial Distance (SD) (mm), the average displacement of the COP trace between one peak and the next one.
The two different APA programs were performed twice a week, for 36 weeks, and every session lasted for 60 minutes. The APA sessions were performed in a gym and conducted by an instructor in groups of a maximum of 20 participants.
Each session of the muscle reinforcement training was divided into three phases: (1) standing 15′ warming up and motor coordination exercises; (2) standing/on the ground 30′ muscle toning at low/moderate intensity for different muscular districts (primarily abdominal and both lower and upper limbs) with low weight loads (0.5, 1, or 1.5Kg); (3) cooling down 15′ and relaxation/stretching of the muscle systems with specific exercises [
Each session of the postural training was divided into three phases: (1) standing 10′-15′ cardiovascular activation, shoulder and coxofemoral joints mobilization, lower limbs reinforcement; (2) sitting 10′-15′ neck and shoulders mobilization; (3) on the ground, 5-30′ spine mobilization, abdominal muscles reinforcement, gluteal and spine extensor muscles reinforcement, spine stretching, hamstring and psoas muscle reinforcement and self-stretching, and final relaxation [
Both muscle reinforcement exercises and postural exercises were adapted to the participant’s abilities and were progressive in repetitions and difficulties over time.
Shapiro-Wilcoxon tests were used to evaluate whether the outcome variables were normally distributed.
SM, SMI, and HGS of the two groups were normally distributed and were compared before (T0) and after (T1) the intervention by means of a repeated measure ANOVA, with TIME (2 levels, T0 and T1), as within-subject factor, and GROUP (2 levels, RESISTANCE and POSTURAL), as between-subject factor. Newman-Keuls post hoc test was used to evaluate significant interactions.
Static balance data of the RESISTANCE and POSTURAL groups acquired with CE and OE were not normally distributed. Therefore, Mann-Whitney tests were used to evaluate differences between groups at each time epoch (T0 and T1), whilst Wilcoxon tests were applied to assess changes in each group. Significance for all procedures was set at a level of 0.05.
Data are presented as mean ± SD for normally distributed data and as median associated with the interquartile range for not normally distributed data.
The statistical analysis on lean mass expressed as % of the total weight and in kg showed a significant effect of the factor TIME (%:
Data concerning skeletal muscle mass (SM) values before (T0) and after (T1) the intervention program are represented in Figure
Values of skeletal muscle mass (SM) (a), skeletal muscle mass index (SMI) (b), and handgrip strength (HGS) (c) of the muscle reinforcement training group (RESISTANCE, black lines) and postural training group (POSTURAL, grey lines) before (T0) and after (T1) the intervention. Values are means ± SE.
The statistical analysis on SMI values showed a significant effect of the factor TIME (
Results of the handgrip test are represented in Figure
The static balance data are represented in Figure
Static balance data expressed as median associated to the interquartile range. CE: closed eyes; OE: open eyes; n.s.: not significant.
| | | |||||
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| | | | | | ||
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| 16.78 | 15.44 | <0.001 | 19.57 | 23.59 | <0.001 | T0: n.s.; |
| 11.76 | 9.75 | <0.001 | 12.13 | 11.23 | n.s. | T0: n.s.; |
| |||||||
| 40.64 | 26.55 | <0.001 | 44.38 | 52.25 | n.s. | T0: n.s.; |
| 19.36 | 12.68 | <0.001 | 18.99 | 17.74 | n.s. | T0: n.s.; |
| |||||||
| 0.65 | 0.87 | <0.001 | 0.59 | 0.48 | <0.05 | T0: n.s.; |
| 1.11 | 1.37 | <0.001 | 0.99 | 1.09 | n.s. | T0: n.s.; |
| |||||||
| 6.71 | 4.65 | <0.001 | 6.19 | 7.70 | <0.01 | T0: n.s.; |
| 3.78 | 2.61 | <0.001 | 3.28 | 3.06 | n.s. | T0: n.s.; |
Static balance data of the RESISTANCE and POSTURAL groups, acquired with closed eyes (CE) and open eyes (OE) before (T0) and after (T1) the intervention. SP: Sway Path; SA: Sway Area; ST: Stay Time, and SD: Spatial Distance. Values are medians ± SE.
Wilcoxon tests comparing the Sway Path acquired with close eyes (SP CE) before and after treatments revealed a significant decrease of its value after muscle reinforcement training (
In the RESISTANCE group Sway Area decreased significantly after the treatment in both conditions (CE:
After the intervention, ST increased significantly only in the RESISTANCE group in both conditions (CE:
In the RESISTANCE group the results of the Wilcoxon tests showed a significant decrease of SD value in both conditions (CE:
The results of this study, performed in moderate sarcopenic older women, demonstrate that the RESISTANCE group showed significant improvements in muscle mass and function after the proposed muscle reinforcement program, whereas no significant differences were found in the POSTURAL group, after the adopted postural training. Furthermore, the muscle reinforcement program was able to induce in RESISTANCE group significant improvements in static balance parameters, whilst no significant differences in these values were found in the POSTURAL group, after the postural training. On the whole, the proposed muscle reinforcement program was able to induce positive effects both on sarcopenia and on postural parameters.
Sarcopenia is closely related to a risk of adverse outcomes, including poor quality of life and impaired ability to perform activities of daily living [
Structured physical activity interventions are known to delay the onset of disability in older adults, improving clinical outcomes such as physical performance, gait speed, overall survival, fall risk, and quality of life [
Two milestone studies have been performed to standardize exercise interventions and elders related outcome measurements [
The SPRINT study was also aimed at assessing longitudinal mobility disability prevention in older adults by virtue of combined nutritional and physical interventions to improve sarcopenia and physical frailty. This study was geared to produce systematic advancements in the management of frail older adults by a multifactorial set of interventions that included physical activity.
A recent systematic analysis has pointed out how exercise interventions are beneficial to body composition and muscle strength [
To overcome this difficulty, we assigned a homogeneous group of seventy-two older women with moderate sarcopenia, according to EWGSOP criteria [
It has been reported that postural control is improved by balance exercise intervention, whereas strength exercises or multicomponent interventions do not significantly influence such postural measurements [
A limitation of this study is the inability to establish a clear dose-response relationship along with individual functional fitness trajectories, due to the lack of baseline comprehensive geriatric assessment and polypharmacy analysis. In addition, the lack of osteoporosis assessment could prevent an accurate evaluation of osteosarcopenia, a common clinical condition in older people correlated with adverse clinical outcomes. On the other hand, the strengths of the study lie in the real-world assessment of an older adult population by a standardized adapted physical approach like that proposed in our APA project. Another limitation of the study is that we did not assess functional improvements in balance after the intervention period. It would be interesting to investigate, in further studies, whether the observed effects after a period of specific muscle reinforcement training are accompanied also by functional improvements.
The present findings show the effectiveness of a muscle reinforcement program on muscle mass and function, as well as on static balance parameters in moderate sarcopenic older women, thus suggesting that this type of intervention could represent a significant approach to reducing important risk factors for falling, such as sarcopenia and balance impairments. However, the limitations of this study and the potential biases must be considered before drawing firm conclusions, and further studies are required to deeply evaluate the effectiveness of different types of adapted physical activity program in muscle mass and function and in balance. On the whole, this study allows moving a step forward in the understanding of the clinical beneficial effects of adapted physical activity in an older population. The longitudinal assessment of this population, including physical activity training adherence over time, that is part of an ongoing study and the inclusion of geriatric assessment parameters will help understanding the elders risk stratification, on the basis of functional fitness and frailty prevention.
The data used to support the findings of this study are available from the corresponding author upon request.
The authors declare that there are no conflicts of interest regarding the publication of this paper.
G. Piastra and L. Perasso contributed equally to the work
The authors acknowledge the entire staff of Ben-Essere: the President Mario Franco Repetto, Dr. Silvia Crispino, Dr. Debora Porzio, Dr. Matteo Ronchi, and all the D-EF Trainers. Their dedication made the setup and operation of the whole program possible.