Feasibility of a community-based Functional Power Training program for older adults
Feasibility of a community-based Functional Power Training program for older adults
Queenie lin ling Tan 2 3
0 Faculty of health and social sciences, singapore Institute of Technology , singapore
1 Department of Psychological Medicine, n ational University of singapore , singapore
2 Frailty research Program, geriatric education and r esearch Institute (gerI) , singapore
3 lilian Min Yen Chye
PowerdbyTCPDF(ww.tcpdf.org) Daniella hui Min n g1 Mei sian Chong 1 Purpose: Community-based programs can increase and sustain physical activity participation in older adults, even for those who are physically frail. We studied the feasibility and potential effect of a 12-week structured Functional Power Training (FPT) program involving high velocities and low loads for older adults conducted in a common area of their housing estate. Patients and methods: The structured FPT program was conducted in collaboration with a health promotion social enterprise and a community service provider based in a public housing site. We recruited nine inactive residents as participants to the single, group-based, twice-weekly program. Attendance and adverse event(s) were recorded throughout the program. The Short Physical Performance Battery, Timed Up and Go (TUG), and 30s Sit-to-Stand tests were used to assess functional outcomes pre- and postprogram. The FRAIL Scale was used to assess their frailty status, and a postprogram experience survey was conducted. Results: Eight subjects (aged 74±10 years) completed the program with an average overall attendance of 90.3%, with at least five participants present for each session. Changes in functional outcomes showed a moderate-to-large effect with significant improvement in TUG (p,0.01). In addition, participants either reversed or maintained their frailty status ( p,0.01). Overall, the program was perceived to be well structured, engaging, as well as providing physical and psychosocial benefits. No exercise-related adverse events occurred during the program, and participants were keen to recommend this program to others. Conclusion: Community-based structured FPT is safe and feasible for frail older adults, with the potential to improve function and reverse frailty status.
multicomponent exercise; frail older adults; functional performance; community-
open access to scientific and medical research
Functional decline leading to dependency is a fear that individuals encounter when
considering old age.1 Mobility impairment in older adults is strongly associated
with muscle weakness and low muscle mass, the hallmarks of physical frailty and
sarcopenia.2 Nevertheless, current consensus proposes that regardless of age, the
neuromuscular system has the ability to adapt to appropriate exercise stimulus.3,4
Physical activity guidelines for adults aged 65 years and older emphasize engaging
in regular resistance training to improve strength and function, manage frailty, and
reduce dependency.5,6 While resistance training engages low-velocity contractions at
50%–80% of maximal strength, power training is characterized by performing the
concentric phase at high velocity (ie, as fast as possible) with a slow eccentric phase to
achieve the greatest benefit of muscular power and strength.7 Power training is effective
and has emerged as an alternative modality to resistance training8 to preserve activities
of daily living that require quick, forceful motions,4,7 even in the most vulnerable group
Clinical Interventions in Aging 2018:13 309–316 309
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of institutionalized adults aged 85 years and more.9 Power
producing capabilities compared to muscle strength in older
adults are strongly associated with performance of daily
tasks, such as getting up from a chair, avoiding oncoming
traffic, climbing stairs, and the ability to recover from a loss
of balance.4,5,7,8,10 Furthermore, muscular power deteriorates
earlier and faster than muscular strength with age.11 Hence,
greater emphasis should be placed on improving muscular
power in older adults.4,7
Despite the widespread benefits of regular exercise,
many older adults face multiple barriers such as mobility
impairment, poor health, fear of falling, lack of social
interaction and support, lack of interest or enjoyment, and bad
weather.12,13 Although the aforementioned studies have
demonstrated that power training can ameliorate muscle
weakness, such interventions often involve the use of
specialist equipment, and may not be practical for
implementation in community settings like housing sites and senior
.vdoepw l.syeon apcrotigvriatmyscethnatetrpsl.a14ceFeumrtphhearmsisoroen, hinigfoh-rvmealoticointyomnoevxeemrecnistes
://sw lona without the use of specialist equipment that can be adopted
tthp rsep by community-dwelling older adults is scarce.
In this study, we examined the feasibility and effects of
conducting a 12-week structured Functional Power Training
(FPT) program within a housing estate. We hypothesized
that a community-based structured FPT program involving
high velocities and low loads using body weight and simple
equipment would be feasible and safe for older adults.
Materials and methods
A structured 12-week FPT program was conducted with
a health promotion social enterprise (ProAge Pte Ltd,
Singapore; http://www.proage.sg) and a community service
provider (Filos Community Services, Singapore; http://www.
filos.sg) based in a public housing site (Chai Chee Estate
in the East Singapore). Filos referred suitable participants
living within the housing site. Eligibility criteria were as
follows: Adults aged 55 years and above, able to ambulate
without personal assistance, and able to comprehend simple
instructions. We excluded participants who had uncontrolled
medical conditions, diagnosed with major depression, severe
audiovisual impairment, progressive degenerative neurologic
disease, or terminal illness with life expectancy ,12 months.
To ensure exercise safety, we administered the Exercise
and Sports Science Australia (ESSA) screening tool to
screen for any contraindication to exercise. Subjects with
positive response to any question(s) in the ESSA screening
tool were referred to a doctor for medical clearance prior to
participation. All participants gave written informed consent
to the study, which was approved by the National Health
Group ethics board.
Tests and measures
Baseline demographics and health status were obtained
using a lifestyle questionnaire, focusing on comorbidity,
medications, falls history, and physical activity levels.
Anthropometric measures of height and weight were
obtained at baseline and postintervention. A series of
functional performance measures included the Short Physical
Performance Battery (SPPB), Timed Up and Go (TUG),
and 30s Sit to Stand (30s STS). A FRAIL Scale
questionnaire was administered to categorize participants into frail,
prefrail, and robust categories.15 At the end of the 12-week
FPT program, participants repeated the physical measures.
In addition, semistructured interviews were conducted upon
study completion to understand participants’ experiences and
adherence factors. Trained researchers from the Geriatric
Education and Research Institute administered the test
procedures and interviews.
Program conduct, feasibility, and safety
Prior to each exercise session, pulse oximetry (ChoiceMMed
OxyWatch MD300C63) was used to measure blood oxygen
levels and heart rate. Participants with blood oxygen levels
below 95% SPO2 were advised against participation in the
session. Other pre-exercise screening criteria included high
resting heart rate,16 abnormal resting blood pressure,17
giddiness, or any form of discomfort. Attendance was recorded
for each session. Program adherence was determined by the
number of exercise sessions attended against the total number
of 24 sessions. We considered the program to be feasible if
attendance was maintained at .50% for all sessions and
averaged .80% per session. We monitored and recorded
adverse events throughout the course of the program.
Program acceptance, engagement, and adherence
A survey was conducted after the physical posttest
measurements were taken to understand participants’
experiences and factors for adherence to the program. The survey
comprised nine questions on program acceptance,
satisfaction, adherence, engagement, and desire for continued
participation, with responses recorded by a four-point
Likert scale (1= strongly disagree, 2= disagree, 3= agree, and
4= strongly agree).
short Physical Performance Battery
The SPPB is a widely used functional performance test,
and has been validated in community-dwelling older
populations.18 The battery comprises the following: 1) timed
Sit to Stand, 2) static balance, and 3) timed 2.44 m walk.19
The timed Sit to Stand test assesses one’s ability to complete
five successful chair rises. A successful chair rise was
constituted by a rise to a full standing position with arms crossed
over the chest. The static balance task had three levels of
difficulty based on foot positioning: side by side, semitandem,
and tandem stance. Participants were required to maintain
their feet position for 10 seconds to proceed to the next level.
The walk test is a timed walk, where participants covered
a distance of 2.44 m at their usual walking pace. For each
component, a score of 0–4 points was awarded based on
individual performance. The maximum total score was 12 points,
where a higher score meant better physical function.
Timed Up and go
The TUG consisted of transfer tasks to assess gait and
balance.20 The test required participants to stand up from
a chair, walk a distance of 3 m (marked with a cone) at a
comfortable pace, turn, walk back, and sit down. Participants
were permitted to use routine walking aids, with no additional
physical assistance given. The test was performed twice,
with the better of two trials recorded.
30-second sit to stand
As a measure of lower extremity endurance, participants
performed as many chair rises to an upright position as
possible in 30 seconds.18 The number of successful chair rises
The FRAIL Scale questionnaire comprised five
components of the frailty phenotype based on self-report: fatigue,
resistance, ambulation, illness, and loss of weight.15 One
point was allocated if the participant responded “yes” in a
component, with the total summed score ranging from 0 to 5
and classified into three frailty statuses: robust (score =0),
prefrail (score =1–2), or frail (score =3–5). The scale has
been validated in different populations in different settings,
including Hong Kong and Singapore, to identify individuals
at risk of adverse health outcomes.21,22
The exercise intervention comprised a 12-week (24 sessions)
structured FPT program comprising high-velocity movement,
balance, and mobility exercises. The sessions were led by a
qualified exercise physiologist from ProAge, and assisted by
staffs and volunteers from Filos and/or Geriatric Education
and Research Institute, with a trainer-to-participants ratio of
at least 1:3. Sessions were held at a public area in the housing
estate, twice weekly for 60 minutes with at least one rest day
between consecutive sessions.
The high-velocity movement training consisted of upper
and lower extremity resistance exercises with focus on
the lower body muscle groups (hip abductors, adductors,
extensors, knee flexors and extensors, ankle
plantarflexors, and dorsiflexors). The balance and mobility exercises
targeted lower body muscles through the inclusion of weight
shifts and reduction of base of support. In each session,
participants performed 5–6 lower body and upper body
resistance exercises, supplemented with two balance and
mobility exercises. Training intensity progressed
according to each participant’s capability, starting from two sets
of 10 repetitions for resistance exercises and two
repetitions of 30 seconds for balance and mobility exercises.
Examples of the intervention exercises prescribed are listed
in Table 1. The 24 sessions were distributed into four
progressive phases: 1) Familiarization, 2) Skill-Up, 3) Training
Gains, and 4) Optimizing Gains. In the “Familiarization”
phase (week 0–2), participants were taught the basic
techniques of the exercises in a seated position and
familiarization of the training protocol. Emphasis was placed on safety
and confidence in executing the exercises in proper form.
In the “Skill-Up” phase (week 3–4), participants performed
a variety of bodyweight exercises in a standing position. The
“Training Gains” phase (week 5–8) included an increase in
exercise intensity with more repetitions and the addition
of resistance bands. The final “Optimizing Gains” phase
(week 9–12) consisted of exercises that required weight
transfers, such as circuit training and standing on unstable
surfaces. Each session was accompanied with music to
enhance adoption and maintenance of the program. To
maximize social interaction and engagement, effective strategies
such as buddy systems and regular positive feedbacks were
Nonparametric Wilcoxon signed-rank test was used to
compare pre–posttest measures. Results from the functional
tests and FRAIL Scale were reported as mean and standard
deviation (SD), and effect size of each test was calculated
using Cohen’s d. Results of the study closure interview
was reported as the percentage of responses for each
question. The breakdown of the FRAIL Scale was reported
as the percentage of participants who responded “Yes” to
Nine participants were enrolled into the program, and the
.vdoepw l.syeon baseline demographics are described in Table 2. The mean
/w u age of the participants was 73±10 years. All participants
tt:sp rson were Chinese and had an average of four chronic illnesses,
h ep with hypertension, high cholesterol level, visual impairment,
from roF arthritis, and diabetes as the top five common comorbidities.
ded More than 50% of the participants relied on some form of
lano mobility aids (canes and motorized wheelchair). According
igA Table 2 Participant demographics (n =9)
to the FRAIL Scale, four participants were categorized as
frail, three as prefrail, and one as robust at baseline.
Feasibility and safety
The program excluded participants who had uncontrolled
medical conditions, or without doctor’s medical clearance
if they failed the ESSA screening tool. Eight participants
completed the 12-week intervention with one dropout after
the sixth session due to personal reasons. Attendance for
every session is reported in Figure 1, with a minimal
attendance of 62.5% in sessions 7 and 9. The mean attendance
rate for the eight completers was 90.3%. Two participants
achieved 100% attendance for the program. The participant
with the lowest attendance rate of 75% was unable to attend
some sessions due to conflict with medical appointments
(a 2-week break for gastric evaluation). Two participants
took 1-week breaks for personal reasons or minor medical
reasons. There were no adverse events related to the exercises
during the program.
Program acceptance and satisfactory
Participants perceived the program to be engaging, with
relevant physical, psychological, and social benefits, which
have likely contributed to adherence (Table 3). The
participants also expressed that they would recommend the
program to others.
Participants showed improvements in all the functional or
FRAIL measures with moderate effects of 0.57 and 0.55
for SPPB score and 30s STS time, respectively, and large
effects of 0.86 and 1.23 for TUG and FRAIL Scale scores,
respectively (Table 4). There were pre–postprogram
reductions in TUG time (13.9±2.5 to 11.8±2.3 seconds; p=0.01)
and FRAIL score (2.0±1.2 to 0.9±0.6; p=0.01).
All frail participants reversed their frail score to the
prefrail category (Table 4). Three participants who were
categorized as prefrail had their frailty score improved with
one participant who reversed into the robust category. The
breakdown of the five components of the FRAIL Scale in
Figure 2 reflects the corresponding improvements in response
to fatigue and mobility components of FRAIL, which were
more pronounced, followed by endurance and weight loss
Frailty is not a contraindication to exercise, but an
important reason to prescribe it.6 Community-based programs
are designed to reach older people in “real-world” settings
outside the traditional health care approach. We found that a
structured FPT program for frail residents based in the public
housing site is feasible and safe.
Frail persons are at risk of disability, falls,
hospitalization, and use of nursing homes; early intervention with
frail persons will improve quality of life and reduce care
burden.23,24 The strong adherence in the program resulted in
significant improvement in physical function. Importantly,
the structured program also showed potential to reverse frailty
in all four frail and one prefrail participants. The
improvement in functional outcomes as measured by TUG (18%)
and SPPB (14%) is comparable to the findings of a recent
review on power training for older persons.9 Although most
of the participants were physically frail or prefrail, program
adherence was high with no report of exercise-related adverse
event. This suggests that structured FPT can be a prescribed
modality of exercise for older adults in replacement of
traditional resistance exercise. As no specialized equipment is
required, these exercises can also be practiced at home over
and above the group-based program.
Research in physical training in frail and/or older adults is
dominated by short-term interventions, producing short-term
gains with little consideration of the long-term maintenance
of functional performance.9 The proportion of people who do
not meet the physical activity guidelines are higher after they
attain the age of 60 years, with marked increases after age
80 years, where nearly half the populations did not meet
the minimal threshold for health.6 With Singapore’s aging
population, it is important to have effective and sustainable
community-based programs to support the long-term
maintenance of physical function of older people. Attendance
for this community-based program was at least 62.5% for
any session, with eight of nine participants completing the
program. The high mean adherence (90.3%) for those who
completed the program can be explained by the survey
results: that the program was well structured, relevant to daily
tasks, engaging, and conferred physical and psychosocial
benefits. The finding that all participants would recommend
the program to others, and all except one would continue to
participate in similar programs, suggests that our structured
FPT program has the potential for wider, sustained
participation. Compared to conventional resistance training, our FPT
program required no specialist equipment for loading and
would be feasible for such a small group-based program in
a housing site, with convenient and easy accessibility for the
residents. Community partnerships demonstrated in this study
would be critical to the sustainability of such a program in a
public housing setting.6,12 The result of this feasibility study
would inform the implementation of a larger-scale
community-based multisite, randomized controlled intervention trial
being planned to target these frail and prefrail individuals,
given their high prevalence in the community.25
From the individual components of the FRAIL scale, the
frail participants reversed to prefrail as they reported “no” to
the mobility question “By yourself, without using any aids,
do you have any difficulty walking to a bus stop?” by the
end of the exercise program. Additionally, all participants
reported that they “do not feel tired most of the time during
the past 4 weeks” to the fatigue question that was a major
contributing factor to the decreased FRAIL score (Figure 2).
This suggests that the structured FPT program resulted in
improved mobility and lesser fatigue.
The improvement in TUG suggests that the FPT program
has the potential to improve balance. Six out of seven prefrail/
frail participants showed a clinically meaningful change in
SPPB score.21,22 When comparing the individual components
of SPPB, the improvement in SPPB scores was mainly
contributed by a faster five times Sit to Stand time and standing
balance, rather than gait speed. This suggests that the
structured FPT has the potential to improve not only muscle
strength but also postural stability.26 Lastly, the training
intensity may not be sufficient to elicit similar improvement
in functional outcomes in the robust participant.
Strengths and limitations
This purpose of this feasibility study is to optimize the
structured FPT intervention. The strengths include the
implementation in a “real-world” housing site setting where
the participants reside, close partnership with local
community providers to engage participation and adherence,
and using simple equipment such as chairs and resistance
bands. However, we felt that the training intensity of the
final “Optimizing Gains” phase could be of greater
intensity and difficulty. Our results are only applicable to this
program and could potentially be different had the intensity
been higher. In addition, an objective measure of physical
frailty such as the Fried phenotype rather than the FRAIL
self-report scale could better quantify the change in frailty
status. Furthermore, we did not conduct a follow-up on the
participants’ fall frequency, an important factor to frailty.
Owing to its small sample size, the study was implemented
as a feasibility study. Thus, we could not make any
assumptions on the effectiveness of the FPT intervention. However,
the data collected would provide information to establish
further investigation. A larger randomized controlled trial
to determine the efficacy of the FPT intervention is
Our study suggests that it is feasible and safe for frail and
prefrail community-dwelling older adults to complete a
structured 12-week high-volume, moderate-intensity FPT
exercise program. Conducting the program in collaboration
with a health promotion social enterprise, and working with
a site-based community service provider, there is potential
for a larger multisite randomized control study to examine
the effectiveness of such a program to improve function and
The authors gratefully acknowledge the partnership and
support of ProAge Pte Ltd and Filos Community Services.
The authors thank Dr Teo Wei Peng (Deakin University,
Australia) for his inputs with regard to the implementation
of the program.
The authors report no conflicts of interest in this work.
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