Here is the design of a clinical trial:

Official Title: Effects of High-protein Diet Combined With Exercise to Counteract Frailty in Pre-frail and Frail Community-dwelling Older Adults: a Three-arm Randomized Controlled Trial

Included conditions:
- Physical Frailty

Study Armgroups:
- {'label': 'Exercise and Protein (EXEPROT)', 'type': 'EXPERIMENTAL', 'description': 'Participants in EXEPROT receive: a high-protein diet combined with Resistance training. The high-protein diet is based on milk-based protein-rich products to supplement the habitual diet (corresponding to a protein intake of 1.5 g/kg/day). 4-day food records are used to estimate the needed protein. Of the shelf-products (e.g. milk, cheese) are used considering the individually preferences. Products are delivered once a week. The training intervention includes progressive explosive type heavy-resistance training two times per week. The intervention runs for 16 weeks. Adherence to the training protocol is monitored at each session. Adherence with the nutrition protocol is monitored daily plus at phone follow-ups where participants are asked about e.g. appetite, weight, habitual intake.', 'interventionNames': ['Other: Resistance training', 'Other: High-protein diet']}
- {'label': 'Protein-only (PROT)', 'type': 'ACTIVE_COMPARATOR', 'description': 'Participants in PROT-group receive the nutritional intervention: The high-protein diet.\n\nThe diet is based on daily milk-based protein-rich products to supplement the habitual diet (corresponding to a total protein intake of 1.5 g/kg/day). The needed amount of protein supplementation is estimated from 4-day food records. Of the shelf-products (e.g. milk, skyr, cheeses) are used considering the individually preferences. Products will be delivered once a week at the home of the participant. The intervention runs for 16 weeks.\n\nAdherence with the nutrition protocol is monitored daily (registration of compliance with the dietary plan) as well as at phone follow-ups where participants are asked about e.g. changes in appetite, weight, and habitual intake.', 'interventionNames': ['Other: High-protein diet']}
- {'label': 'Recommendations (REC)', 'type': 'ACTIVE_COMPARATOR', 'description': 'Participants in the REC-Group receive the comparative intervention: Recommendations.\n\nThe official national dietary recommendations for adults \\>65 years, developed by the Ministry of Environment and Food of Denmark, and related materials is given to the participants and they are encouraged to follow the guidelines (recommending a protein intake of 1.0-1.3 g/kg/day). The intervention runs for 16 weeks.\n\nDuring the intervention all groups will receive two seminars on specific topics related to healthy ageing (e.g. talks on physical activity, sedentary behaviour, and nutrition).', 'interventionNames': ['Other: Recommendations']}

Interventions:
- {'type': 'OTHER', 'name': 'Resistance training', 'description': 'Supervised progressive explosive type heavy-resistance training two times per week', 'armGroupLabels': ['Exercise and Protein (EXEPROT)']}
- {'type': 'OTHER', 'name': 'High-protein diet', 'description': 'Daily supplementation with milk-based protein-rich products', 'armGroupLabels': ['Exercise and Protein (EXEPROT)', 'Protein-only (PROT)']}
- {'type': 'OTHER', 'name': 'Recommendations', 'description': 'Provided with the official national recommendations on nutrition', 'armGroupLabels': ['Recommendations (REC)']}

Primary Outcomes:
- {'measure': 'Changes from baseline lower leg muscle power at 4 months', 'description': 'Lower leg muscle power will be assessed unilaterally using the Nottingham Leg Rig', 'timeFrame': 'Baseline and 4-month follow-up'}

Please estimate the sample size based on the assumption: 
The study assumes a significance level of 0.05, a power of 0.8, and a dropout rate of 25%.
Sample size determination
        Muscle power is the primary outcome of this study. Due to lack of studies comparable to this study design (e.g., age and frailty status of the participants, type of exercise and level of protein supplementation), we have calculated sample size using a combination of studies and methods. Based on findings by BechshÃ¸ft et al. [36], the effect of 12Â weeks of protein supplementation (two daily supplements of 20âg milk protein) in combination with resistance training in +â80-year-old healthy adults increased muscle power by 15% (SEM Â±â5%) in comparison with ââ7% (SEMâÂ±â6%) in the control group (receiving protein supplementation only). In the study by Park et al. [37], 12âweeks of protein supplementation (0.8âg/kg/day, 1.2âg/kg/day, or 1.5âg/kg/day) to pre-frail or frail older adults above 70âyears resulted in an increase in muscle mass (estimated by DXA) of approximately 4% in the group receiving 1.5âg/kg/day. Unpublished data from our own group shows that change in muscle mass (estimated by DXA) accounted for 1.95% of the change in muscle power (power-rig) in older adults following 12âweeks of explosive resistance training. Hence, the estimated effect of an increase in muscle mass of 4% on muscle power is 7.8%. Adding this to the results from BechshÃ¸ft et al. [36] gives us an estimated change on 0.8% in the PROT group. Assuming that the change in muscle mass are comparable in the three groups, we therefore expect a change in muscle power of 15%, 0.8%, and ââ7% with a SD of 30 in the EXEPROT, PROT, and REC groups, respectively.
        Setting a power of 0.8 a sample size with 37 participants in each arm should be enough to detect a significant difference in muscle power (significance level at 0.05). Adding 25% to account for dropouts a total of 150 participants is needed.
        Strength calculation was made in PASS 14.