Article Text

Protocol
Intervention of muscle-building and antifrailty exercise combined with Baduanjin for frailty of different functional levels: study protocol for a randomised controlled trial
  1. Shuaixuan Xu1,2,
  2. Zhuyun Gong3,
  3. Fang Wang1,4,
  4. Mengyu Cao1,
  5. Jinwei Liu1,4,
  6. Chao Chen1,4,
  7. Nihui Zhang1,4,
  8. Jingwen Kang1,
  9. Chuang Xu1,4,
  10. Nan Peng1
  1. 1Department of Rehabilitation Medicine, The Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Beijing, China
  2. 2Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, Henan, China
  3. 3Department of Outpatient, The Second Medical Center & National Clinical Research Center for Geriatric Diseases, Chinese PLA General Hospital, Beijing, China
  4. 4Graduate School, Chinese PLA General Hospital, Beijing, China
  1. Correspondence to Dr Nan Peng; pengnan301{at}163.com

Abstract

Introduction Frailty has been currently considered as a multidimensional concept, including physical, cognitive and social frailty. Frailty has also been associated with a range of adverse events, which might increase the risks of disability, falls, fractures, delirium and death. Increasing evidence has shown that multicomponent exercise training can improve physical and cognitive function, delay or reverse frailty. However, there is still a lack of exercise intervention programmes for the frail older adults in China. This trial aims to investigate the effects of the muscle-building and antifrailty exercise combined with Baduanjin on the physical function of frail older adults, as well as the effectiveness and safety of the intervention.

Methods and analysis This study is a prospective randomised controlled trial. A total of 192 patients, aged 70 years or older, who are diagnosed as prefrailty or frailty based on the Fried criteria will be included. Prior written and informed consent will be obtained from every subject. These subjects will be randomly assigned to the exercise intervention group (n=96) and the control group (n=96). The exercise intervention group will undergo different exercise programmes for different levels of physical function. They will perform the muscle-building and antifrailty exercise three times per week for 30–60 min for 24 weeks. The control group will implement health education on frailty and maintain the old lifestyle without any intervention.

The primary outcomes include the change in frailty and functional capacity, assessed according to the Fried Scale and the Short Physical Performance Battery. Secondary outcomes include the changes in body composition, Activities of daily living, Mini-Mental State Examination, The Geriatric Depression Scale-15 and the haematological indicators.

Ethics statement The study has been approved by the Medical Ethics Committee of the PLA General Hospital (approval no.: S2022-600-02).

Trial registration number ChiCTR2300070535.

  • GERIATRIC MEDICINE
  • Protocols & guidelines
  • Health Services for the Aged
http://creativecommons.org/licenses/by-nc/4.0/

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

STRENGTHS AND LIMITATIONS OF THIS STUDY

  • To our knowledge, this is the first exercise intervention programme for the frail older adults based on different levels of physical function in China. Additionally, Baduanjin is combined with multicomponent exercise, and thus developed muscle-building and antifrailty exercise with Chinese characteristics.

  • The older adults can learn and memorise specific movements more conveniently by watching videos or sports cards.

  • This study observes the effectiveness of exercise intervention through multidimensional indicators and explores the circulation factors associated with frailty after exercise intervention.

  • If our results are positive, they will be helpful for the further promotion of muscle-building and antifrailty exercise and will provide important strategies for the prevention and treatment of frailty in China.

  • A major limitation of this study is the sample size. Since there are few studies on frailty intervention in China, the sample size is estimated based on foreign works.

Introduction

Frailty is a reduction in the physiological reserve function of the older adults, manifested by the deterioration of the physiological functions of multiple organs and/or systems. It has been characterised by the increased vulnerability to stressful events, which can lead to a range of adverse events (AEs) (ie, the exacerbation of chronic illness, rehospitalisation, falls, delirium, dementia, disability and even death) when exposed to minor stimuli, such as the respiratory infection and the minimal surgery).1–3 A systematic review has analysed the prevalence of frailty in 1 755 497 people aged 50 years or older from 62 countries, and found that the prevalence of frailty increases with age, from 20% in people aged 70–79 years, to 31% in those aged 80–89 years and 51% in those aged 90 years and older.4 Frailty affects chronic disease, medications and perioperative patient outcomes, elevating the burden of long-term care.5 The biological mechanisms of frailty have not been fully understood, which have been currently regarded to be caused by multisystemic and multifactorial disorders, mainly induced by the chronic inflammation, oxidative stress, mitochondrial dysfunction, insulin resistance, reduced hormone levels and dysbiosis of the gut flora.6 Defining the pathogenesis of frailty is essential for development of effective frailty interventions and individualised treatment.

Frailty is a dynamic process. Individuals may evolve from healthy, prefrailty, frailty and then disability, which could be reversed to some extent with early intervention.7 Early identification and intervention of frailty may have positive effects on the disease prognosis. Current interventions for frailty mainly include the exercise, nutritional treatment, comorbidity interventions and medication management. The effectiveness of interventions varies, depending on the use of different frailty assessment tools, duration, intervention modality, gender and residential status.8 Increasing evidence has shown that older people who are physically inactive are at increased risk of developing chronic diseases (such as the hypertension, diabetes, sarcopenia, depression and cancer), and regular exercise has become one of the key measures to prevent chronic diseases and functional impairment.9 A previous study has shown that the life expectancy would be increased by 3 years when exercise starts at age 85.10

Exercise intervention, as one of the most important interventions, can improve physical function, gait capacity, balance, cardiorespiratory capacity and muscle strength, while can reduce the risk of falls and disability.11–13 There is no evidence in the literature concerning which exercise are more effective for frailty, but it has been widely accepted that multicomponent exercise represent satisfactory treatment options, including the resistance, aerobic, balance and flexibility exercise.14 Resistance training (RT) has been shown to be an important strategy to improve muscle mass, muscle strength and functional capacity.15 Lung capacity and cardiorespiratory endurance decline with age, accompanied by the mitochondrial dysfunction, oxygen exchange limitation and decreased ability of muscles’ usage of oxygen in frail older adults. Aerobic training can help older people improve the cardiorespiratory endurance and increase the oxygen uptake.16 Balance and flexibility training are also important exercise forms. Balance involves the muscular, skeletal, joint and neuropsychological functions of the body. Wijlhuizen et al have studied 1752 subjects aged 65 years and older, and the survey has shown that at least 22% of older adults restrict their activities due to fear of falling, and those afraid of falling are more likely to restrict their activities. Improving balance in older people is important for preventing falls.17 A vivi-frail exercise intervention study has shown significant improvements in the Short Physical Performance Battery (SPPB), grip strength, and cognition and depression in cognitively frail older adults after 3 months of intervention.18 Sadjapong et al have conducted a multicomponent exercise intervention study in the frail older adults, which has shown some improvement in the grip strength, the TUG (Timed Up and Go) test, and balance function, and the IL-6 and C reactive protein levels are reduced after 3 months of intervention.19 Exercise training increases the levels of free testosterone and growth hormone, and promotes the IGF-1 expression in skeletal muscle.14

Although some investigation has shown the effectiveness of exercise intervention for frailty, there still lacks evidence concerning exercise intervention programmes appropriate for Chinese older adults. As an excellent traditional health exercise with a long history in China, the Baduanjin has unique advantages in strengthening the body. The Baduanjin can be used to optimise and balance the energy in the body by adjusting the breathing, and controlling body postures and meditation, which might regulate the functions of the internal organs, unblock the meridians, strengthen the body, eliminate illnesses and slow down the ageing process.20 The Baduanjin includes a variety of exercise elements, incorporating the strength, balance and flexibility training. It has been well documented that the Baduanjin is effective in strengthening muscles, improving balance, preventing falls and improving depressive symptom and cognition.

Therefore, in our study, the first, second, fourth and eighth ‘duan’ of the Baduanjin, which are more suitable for the frail older adults are selected. The movements that may cause dizziness and falls are removed. These selected four movements include the ‘prop up the sky by two hands’, ‘draw a bow on both sides’, ‘look back and forwards’, and ‘rise and fall on tiptoe’, which will help to stretch the muscles and bones, unblock the meridians and regulate the breathing. The above movements are uesd as the warm-up and relaxation exercise to practice balance and flexibility. Meanwhile, a set of muscle-building and antifrailty exercise is designed for older adults with different levels of physical function combined with effective multicomponent exercise programmes.

This study aims to investigate whether this exercise will improve the physical function of frail or prefrail older adults, and whether it will reverse the frailty and improve the quality of life of the older adults. A prospective randomised controlled trial is designed to assess the effectiveness and safety of muscle-building and antifrailty exercise. The trial aims to determine the effects of muscle-building and antifrailty exercise on the physical function of older adults with frailty. In addition, the effects of the muscle-building and antifrailty exercise on the cognition, depressive symptom and inflammation status of the older subjects will be analysed. The effectiveness of the intervention will be further verified from several respects.

We hypothesise that by assessing Fried score, SPPB, haematological indicators, and cognitive, emotional scales, the muscle-building and antifrailty exercise intervention group will have improvements in the frailty status and the physical function, while the control group will not demonstrate significant improvement.

Methods/design

Study design

This study adopted a prospective randomised controlled design and was conducted on 1 February 2023 and will end on 1 June 2024. Patients who meet the inclusion criteria will be randomly assigned to either the intervention or control group. Primary outcome (Fried score and SPPB), body composition, cognitive function, depressive symptom, self-care ability will be measured at baseline, week 12 and week 24, respectively, while the haematological indicators will be measured at baseline and at week 24. The study protocol and outcome assessment schedule are outlined in figure 1 and table 1.

Table 1

Assessment, intervention schedule for study participants

Patient and public involvement

None.

Study subjects

Fried criteria: Frailty Phenotype scale was first proposed by Fried et al, which requires an instrument for quantitative measurement. The scale contains five criteria: unintentional weight loss during the past year, self-reported exhaustion, weakness (grip strength), slower walking speed, and low physical activity. Prefrail is defined when 1–2 following criteria are met, while frail is defined when 3 or more criteria are met.21

Inclusion criteria

  1. Age 70 years or older.

  2. Diagnosed as frail or prefrail.

  3. Voluntary participation in the trial with signed informed consent form.

Exclusion criteria

  1. Severe cognitive impairment.

  2. Severe loss of vision or hearing that prevents normal communication.

  3. Patients who suffer from a major illness or undergo major surgery within the last 6 months and have not recovered.

  4. Acute stage of various diseases or severe functional failure, such as acute infection, gastrointestinal bleeding, heart failure, respiratory failure, renal failure, etc.

  5. Patients with diabetes (fasting blood glucose level >125 mg/dL), hypertension, heart disease without effective control.

  6. Patients whose functional tests are affected by pain in the joints, bones and muscles of the extremities.

  7. Patients with metal implants in the body such as pacemakers and artificial joints.

Recruitment

Recruitment in the community health service centre, distribution of brochures, screening and communication of patients, determination of eligibility and signing of informed consent are conducted prior to baseline assessment.

Intervention group

The frail or prefrail older adults will be assigned to different exercise programmes according to their levels of physical function, including the functional independence and assistive walking. Functional independence refers to older adults who can walk independently. Assistive walking refers to older adults who usually walk with the help of another person or an assistive device.

  1. The independent walking group

    1. Warm-up exercise: Four movements from the Baduanjin, including the ‘prop up the sky by two hands’, ‘draw a bow on both sides’, ‘look back and forwards’ and ‘rise and fall on tiptoe’.

    2. Resistance exercise: Six movements, including the incline pull, standing chest press, arm flexion, straight leg raise, single leg stand and sit-stand training; the rest 10–15 times/set, 1–3 sets.

    3. Aerobic exercise: brisk walking exercise requires the whole body to relax and walk naturally at a slightly faster pace than usual, with naturally breathing. The walking speed is adjusted according to the subject’s condition to achieve slightly sweating. The duration is 20–30 min, with appropriate rest between. The exercise ends with slight fatigue.

    4. Balance exercise: single leg stand, 10–30 s/set on each side, 1–3 sets. Yangko dance is a popular rural folk dance in China, in which Yangko step is one movement (10 times/set for 1–3 sets).

    5. Relaxation exercise: same as the warm-up exercise (see figure 2 for the above movements).

  2. Disability-the assistive walking group

    1. Warm-up exercise: Four movements from the Baduanjin, including the ‘prop up the sky by two hands’, ‘draw a bow on both sides’, ‘look back and forwards’ and ‘rise and fall on tiptoe’.

    2. Resistance exercise: Six movements, including the incline pull, chest press, arm flexion, sit-stand training, squat training, straight leg raise and single leg stand. The strength of the elastic band and the weight of the sandbag can be adjusted according to the subject’s condition. Single leg stand, 10–30 s/set on each side, 1–3 sets; and the rest 6–12 times/set, 1–3 sets.

    3. Aerobic exercise: Stepping in a sitting position while performing chest expansion, throwing punches, turning hand and slapping leg; 2–4 sets of 8 beats/group, 2–4 sets.

    4. Relaxation exercise: Same as the warm-up exercise (see figure 3 for the above movements).

Figure 2

Movements of the independent walking group.

Figure 3

Movements of disability—the assistive walking group.

Exercise intensity

Medium intensity is recommended, using the Borg’s rating of perceived exertion (RPE) Scale (with the Borg 11–13 being the appropriate exercise intensity).22 Performance is characterised by no breathlessness during exercise, slightly sweating and the ability to communicate normally with those around.

Caution

  1. Specific movements and repetitions will be adjusted according to the functional condition.

  2. Subjects in poor functional condition may practice empty hand adaptation for 1–2 weeks.

  3. The recommended length of the elastic band is 1.2 m, which should be wrapped around the hand at least once during exercise to prevent loosening of the elastic injury.

  4. The starting elastic band and sandbag weight should be chosen so that the person could complete each set of repetitions several times and then feel tired, finding it difficult to continue, generally starting with a yellow Thera-Band and a unilateral 0.5 kg sandbag. The next level of Thera-Band and sandbag can be tried after 6 weeks or when the subjects feel relaxed after completing the maximum number of repetitions and sets.

  5. It should be recommended to have a person leading the exercise and adjusting the training pace, with another staff member around to help correct movements, observe the subject’s status and deal with any unexpected AEs.

  6. Heart rate, pulse oxygen and blood pressure will be tested during the training according to the conditions.

In order to ensure that participants can master the movements, we will ask professional rehabilitation doctors to provide initial guidance on the specific movements of the participants. Participants can also log in to the public platform provided by us to learn the specific movements in conjunction with the video tutorials. At the same time, in order to ensure the quality of exercise completion for participants, exercise instructors will supervise and guide the exercise during each session, and will keep detailed records of the participants’ exercise completion; those who fail to complete the exercise as required will also be recorded with specific reasons and encouraged to adhere to the intervention. Participants will also be provided with an exercise diary to register and monitor adherence to the self-management intervention. Participants will be rewarded for adhering to the intervention in order to promote motivation to exercise. Throughout the intervention period, if participants have any questions about the exercises, they will be able to provide feedback to the research assistant, who will resolve them in a timely manner.

Control group

The control group will keep their original exercise habits unchanged and will be educated once a week about prevention and rehabilitation of frailty, receiving no other exercise training.

Outcome assessment

Basic information

Basic information of these participants will be collected based on a self-designed study medical questionnaire, including the age, gender, ethnicity, education, exercise habits, marital status, living alone or not, smoking and drinking habit, occupation and socioeconomic status, as well as the type and number of chronic diseases and medications they took.

Primary outcomes

  1. Fried score: assessed using the Fried scale.21 This scale is suitable for both the scientific and clinical applications and can reflect the state of frailty, which is commonly used assessing scale for frailty.

  2. Functional measures: Functional capacity will be assessed by the Short Physical Performance Battery (SPPB), which includes the five-time chair stand time test, balance test, and eight-foot walking speed. The SPPB score ranges from 0 (worst) to 12 (best), with a total score of less than 10 indicates frailty.23 24 The SPPB is a good indicator of physical function, which has been shown to be an effective predictor for AEs (such as falls, disability and death).

The physical function tests involved in the above items are as follows: (1) Grip strength: The JARMA Plus is used to measure the dominant hand twice, and the maximum value is taken.25 (2) Gait speed: The subject will be asked to walk 10 m at normal speed, starting the timer when their forefoot tiptoe crossed 2 m, and ending the timer at 8 m. The time required to walk 6 m will be recorded and the gait speed will be calculated. (3) The five-time chair stand time test: the subject will be asked to repeat, from sitting to standing, five times and the time taken will be recorded. If the subject could only stand with the help of a handrail or with the help of an arm to support the other parts of the body, he/she will be evaluated to be unable to complete the test.26

Secondary outcomes

Body composition

Skeletal muscle indicators include the SMI (Skeletal Muscle Index) and bone mineral content. The fat-related indicators include the body fat mass, body mass index, visceral fat area, basal metabolic rate, etc. Nutritional indicators include the protein and mineral contents. The above indicators will be tested using the Direct Segmental Multifrequency Bioelectrical Impedance Analysis (InBody770, Korea). The SMI will be corrected for height, which is the ratio of the sum of skeletal muscle mass of the extremities to the square of the height.

Self-care abilities

Self-care abilities was assessed using the Katz index of independence in ADLs (activities of daily living), which includes the following six items: bathing, eating, transferring from bed to chair, using the toilet, walking and dressing, each of which is scored with 0 or 1, depending on whether the participant is able to complete the activity with or without help.27

depressive symptom and cognitive function

The Geriatric Depression Scale includes 15 items, which can effectively reflect the emotional state of older adults, with 0–5 items defined as normal, 5 or more positive items as mild depression, and 10 or more as major depression.28 The MMSE (Mini-Mental State Examination) is developed by Folstein et al to test the orientation, immediate memory, attention and calculation, reading, verbal skills and drawing skills of older adults.29 The MMSE is an indicator of the cognitive ability of older adults.

Hematological indicators

Haematological indicators mainly include the blood count, blood biochemistry, vitamin D, IGF-1, cystatin Cand inflammatory factors (IL-6, TNF-α, CXCL-9, etc)

Safety measurements

Screening of high-risk population and fall prevention safety education will be carried out. Prior to the intervention, participants will be assessed before exercise, including their medical history, such as whether they have signs or symptoms of cardiovascular, metabolic or kidney disease, exercise habits, and musculoskeletal and joint pain. During the intervention, the occurrence of AEs will be monitored, and the causality of the intervention and the severity of AEs will be assessed. AEs are defined as adverse or unanticipated signs, symptoms or diseases that occur during the intervention, such as falls, sports injuries, etc, with uncertainty. The occurrence of any AEs will be recorded in detail on the case report form (CRF). If serious AE occurs, the lead researcher will be notified within 24 hours, and the rehabilitation physician will give proper resolution as soon as possible. This information will be recorded in the original file. Serious adverse risk events associated with the intervention will be reported to the PLA General Hospital Ethics Review Committee.

Randomisation and blinding

Following the baseline assessment, all eligible participants will be randomised according to the on-line randomisation procedure (www.randomizer.org). Randomisation into the intervention and control groups will be carried out at the ratio of 1:1. We cannot blind participants, exercise instructors or intervention supervisors to the assigned intervention programme, but outcome assessors are assured that they have no knowledge of how participants are grouped, or what outcomes are expected in these two groups.

Sample size

The sample size will be calculated based on the change in SPPB scores. The study is divided into the intervention and control groups, with equal sample size for each group. According to the published literature,18 after 3 months of intervention, the difference in SPPB scores between the exercise intervention and control groups was 1.4, assuming an SD of σ=2.7, a power of 90% and α of 0.05. A sample size of 80 cases was calculated by the PASS V.15, taking into account a 20% shedding rate, resulting in the inclusion of 96 cases in each group and a total of 192 cases herein. The study team will focus on instructing assessors at each centre to regularly screen and assess in order to achieve the target sample size. If the expected sample size is not met, the inclusion period will be extended for further 3 months.

Statistical analysis

SPSS V.26.0 software will be used for statistical analysis. The P<0.05 on both sides indicated statistical significance. Normally distributed measures will be expressed as the mean±SD, non-normally distribution ones will be expressed as median (interquartile) (M (Q1, Q3)), and categorical variables will be described as frequencies and percentages n (%). T-test for multiple independent samples will be used for comparison between groups of normally distribution. Mann-Whitney U test will be used for comparison between groups of non-normally distribution. A χ2 test will be used for comparison between groups of categorical variables. Analysis of variance will be used to compare the mean change in continuous variables between the two groups. The missing data will be filled in using the multiple imputation method.

Data collection and management

The CRF will be completed by outcome assessors. Then, research assistants will transcribe the CRF data into EDC system, and other users of the system (investigators, clinical supervisors, data managers), etc can see the data updates on the system in real time. The EDC system is a hardware and software platform with the ability to generate eCRFs. Study data will be stored in a separate password-protected location in the EDC system. Data monitoring committee formed by at least two clinical experts and one clinical trial statisticians, who are independent of the sponsor and have no competing interests. DCM is primarily responsible for periodically reviewing cumulative data from ongoing clinical trials to protect subject safety, ensure trial reliability and validity of trial results. DCM will have access to these interim results and make the final decision to terminate the trial.

Ethics issues

The study is approved by the Medical Ethics Committee of the PLA General Hospital (approval no. S2022-600-02). The investigator is responsible for recruiting subjects and speaking with subjects or their guardians. It is the responsibility of the investigator to explain to the subjects the details related to the clinical trial, to inform the subjects of the possible benefits and risks, and to obtain signed and dated informed consent from the subject or his/her guardian (Informed consent from are shown in online supplemental file 1). The investigator or other personnel involved in the trial should not force or otherwise improperly induce the subjects to participate in the trial. Modification of the protocol after recruitment of the first participant will not be allowed unless necessary and additional ethical approval will be required. This clinical trial is designed in accordance with the current requirements related to the conduct of clinical trials in hospitals in China, referring to the International Conference on Harmonisation-Good Clinical Practice, and in compliance with the Declaration of Helsinki and related regulatory requirements.

Dissemination

Our findings will be spread through training sessions for online and offline delivery, presentations at conferences and articles in peer-reviewed journals. The findings will also be spread to researchers, medical practitioners, healthcare workers and the general public. The results of the study will be distributed to the subjects in the form of a written report.

Discussion

The latest population survey in China has shown that there are 264 million people aged 60 years and above, accounting for 18.70%, among whom there are 190 million people aged 65 years and above, accounting for 13.5%, and the level of ageing is expected to exceed 30% by 2040.30 In 2020, the number of disabled people in China reaches 52.71 million, and the number of older adults disabled people is expected to reach 77.65 million by 2030.31 Frailty has been considered as a precursor to disability, and the investigation concerning the effective intervention programmes to slow down the onset of frailty and its progression to disability has become a major focus of clinical research. As a traditional Chinese exercise, Baduanjin has become one of the most popular exercises for the older adults in China. It not only improves physical function, but also regulates depression and anxiety, improves cognitive function and delays ageing.32 33 Taijiquan, another traditional Chinese exercise, is a moderate aerobic exercise that requires a certain level of exercise skill, which is more difficult for frail and cognitively impaired older adults to master. We have selected the simple, safe and effective movements from the Baduanjin to integrate into the exercise intervention programme as balance and flexibility training. It also combines resistance and aerobic exercise to design muscle-building and antifrailty exercise with Chinese characteristics for frail older adults with different levels of physical function. To ensure that the participants could master the movements of the muscle-building and antifrailty exercise, a professional rehabilitation practitioner will be asked to give participants initial instruction on the specific movements. Specially trained instructors will supervise and guide the exercise during each session. Furthermore, a public platform has been developed for rapid screening and intervention of frailty. After assessing the frailty state and physical function of the participants, the rehabilitation practitioner will assign different exercise programmes according to the different levels of function. The user interface of the patients will display the corresponding exercise programmes with detailed movement analysis, video teaching content and exercise punch card records. Thus, the participants can memorise the movements. The public platform will also regularly publish information on frailty. A set of exercise cards have been designed to make it easy for those older adults in rural areas who do not know how to use tools such as mobile phones or those with low literacy levels.

This study aims to observe the effectiveness of the muscle-building and antifrailty exercise intervention especially in terms of physical function and explores the circulation factors associated with frailty after exercise intervention. In addition to the Fried score and SPPB, the evaluation of several dimensions (including cognitive, emotional, ADLs and laboratory indicators) will provide a possibility to explore the effectiveness of the muscle-building and antifrailty exercise intervention. The unique feature of this study is the self-developed muscle-building and antifrailty exercise with Chinese characteristics according to different levels of physical function, which has been detailed and carefully designed by experts in the field of geriatric and rehabilitation, and will not be restricted by venue and can be exercised at home, community centre, nursing house and hospitals. If this exercise programme is effective in improving physical function in the frail older adults, and potentially effective in improving depressive symptom, cognition and circulation factors, it will help to further popularise and integrate into clinical practice. Second, another important expected outcome of our project is the promotion of exercise prescription in frail older adults to prevent disability and improve the quality of life of the older adults. Finally, due to the lack of effective exercise programmes that fit for the frail older adults population in China, our findings may be an important step forward in providing accurate exercise prescriptions for the frail older adults.

Ethics statements

Patient consent for publication

References

Supplementary materials

  • Supplementary Data

    This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.

Footnotes

  • SX, ZG and FW contributed equally.

  • Contributors NP, SX, ZG and FW conceived the study protocol, participated in the drafting of manuscripts, SX wrote the manuscript, NP revised and finalised the study protocol. MC, JL, CC, NZ, JK and CX helped to develop the study measures and analyses. All authors are responsible for revising the manuscript and approving the final version.

  • Funding This work was supported by the National Key Research and Development Program of China, grant name 2018YFC2002004 and 2018YFC2002000.

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.