The SPRINTT study will evaluate the efficacy of a multicomponent intervention programme (physical activity, nutritional counselling/dietary intervention, and information and communications technology intervention) compared with a healthy aging lifestyle education programme on mobility disability, in non-disabled older people with physical frailty and sarcopenia.

As the life expectancy in European countries continues to increase, the maintenance of physical independence in older persons has become a major public health priority. The ability to ambulate without assistance is crucial for independent living and it is often the first ability to be lost in the process leading to disability. Older people who have impaired walking function need more assistance and are more likely to be placed in nursing homes, have a higher risk of morbidity, mortality and hospitalisation, and experience a reduced quality of life. The ultimate goals of the Sarcopenia and Physical fRailty IN older people: multicomponenT Treatment strategies (SPRINTT) project are to offer efficient treatment options, based on a multicomponent intervention including physical activity, nutrition and information and communications technology, to physically frail, sarcopenic older persons and to improve their quality of life. The result will directly contribute to the long-term sustainability and efficiency of health- and social-care systems. The conceptualisation of physical frailty and sarcopenia (PF&S) as proposed in SPRINTT will promote significant advancements over the traditional approaches by enabling the precise operationalisation of the condition, a clear identification of the affected population and the rapid translation of findings to the clinical arena.

Inclusion criteria:

1. Short Physical Performance Battery (SPPB) score between 3 (included) and 9 (included);

2. Able to complete the 400-m walk test within 15 min without sitting down, help from another person, use of a walker, or stopping for more than 1 minute at a time;

3. Presence of low muscle mass based on Dual Energy X-Ray Absorptiometry (DXA) scan, according to the Foundation for the National Institutes of Health Sarcopenia Project (FNIH) criteria:

   • Body mass index-adjusted appendicular lean mass (aLM; i.e., the sum of lean mass from both arms and legs): <0.789 in men, and <0.512 in women OR
   • aLM <19.75 kg in men and <15.02 kg in women

4. Willingness to be randomised to either intervention group and to follow the study protocol.

Exclusion criteria:

General

1. Unable or unwilling to provide informed consent or accept randomisation to either study group.
2. Plans to relocate out of the study area within the next 2 years or plans to be out of the study area for more than 6 consecutive weeks in the next year;
3. Residence in long-term care;
4. Household member enrolled in the study.

Clinical conditions:

1. Current diagnosis of schizophrenia, other psychotic or bipolar disorder;
2. Consumption of more than 14 alcoholic drinks per week;
3. Difficulty communicating with the study personnel due to speech, language, or (non-corrected) hearing problems;
4. Mini Mental State Examination lower than 24/30;
5. Severe osteoarthritis (e.g., awaiting joint replacement) that would interfere with the ability to participate fully in either study arm;
6. Cancer requiring treatment in the past 3 years, except for non-melanoma skin cancers or cancers that have an excellent prognosis (e.g., early stage breast or prostate cancer);
7. Lung disease requiring regular use of supplemental oxygen;
8. Inflammatory conditions requiring regular use of oral or parenteral corticosteroid agents;
9. Severe cardiovascular disease (including New York Heart Association class III or IV congestive heart failure, clinically significant valvular disease, history of cardiac arrest, presence of an implantable defibrillator, or uncontrolled angina)
10. Upper and/or lower extremity amputation;
11. Peripheral arterial disease Lériche-Fontaine 3 or 4;
12. Parkinson's disease or other progressive neurological disorder;
13. Renal disease requiring dialysis;
14. Chest pain, severe shortness of breath, or occurrence of other safety concerns during the baseline 400-metre walk test;
15. Current participation in a structured exercise programme, physical therapy or cardiopulmonary rehabilitation;
16. Current enrolment in another randomised clinical trial involving lifestyle, nutrition, or pharmaceutical interventions;
17. Other medical, psychiatric, or behavioural factors that in the judgment of the principal investigator may interfere with the study participation or the ability to autonomously follow either the multicomponent or the healthy aging lifestyle education programmes;
18. Other illness of such severity that life expectancy is expected to be less than 12 months;
19. Clinical judgment concerning safety or non-compliance.

Temporary exclusion criteria

1. Uncontrolled hypertension (systolic blood pressure >200 mm Hg, or diastolic blood pressure >110 mm Hg);
2. Uncontrolled diabetes with recent weight loss, diabetic coma, or frequent hypoglycaemia;
3. Hip fracture, hip or knee replacement, or spinal surgery in the past 6 months
4. Serious cardiac conduction disorder (e.g., third-degree heart block), uncontrolled arrhythmia, new Q waves within the past 6 months or ST-segment depression (>3 mm) on the electrocardiogram;
5. Myocardial infarction, major heart surgery (i.e., valve replacement or coronary bypass graft), stroke, deep vein thrombosis, or pulmonary embolism in the past 6 months;
6. Use of growth hormone, oestrogens, progesterone, or testosterone supplementation in the past 3 months.