Here is the design of a clinical trial:

Official Title: High Intensity Training and Energy Management Education vs. Standard Training and Muscle Relaxation, to Improve Quality of Life in Persons With Multiple Sclerosis, a Randomized Controlled Superiority Trial With Six Months' Follow-up

Included conditions:
- Multiple Sclerosis

Study Armgroups:
- {'label': 'High-intensity interval training + energy management education', 'type': 'EXPERIMENTAL', 'description': '* High-intensity interval training (HIIT): physiologically defined heart rate-controlled cycling with 80-100 rounds per minute (rpm) at 95-100% of maximum heart rate (HRmax). Participants will perform 5 × 1.5-min high-intensive exercise bouts at 95-100% of their HRmax followed by active breaks of unloaded pedalling over 2 min with the aim to achieve 60% of HRmax.\n* Energy management education (IEME): face-to-face education sessions of 6.5 h in duration over a 3-week period, all conducted by a trained occupational therapist. Participants acquire knowledge and understanding about factors that influence energy and the consequences of fatigue on their habits and lifestyle. Six weeks after returning home, the participants will receive a reinforcement letter in the form of information material to remember the content of the IEME and to reinforce the implementation of the behaviour change in managing energy.', 'interventionNames': ['Behavioral: Endurance Training', 'Behavioral: Education']}
- {'label': 'Low-intensity training + progressive muscle relaxation', 'type': 'ACTIVE_COMPARATOR', 'description': "* Low-intensity training (ST): participants will exercise for 24 min continuously at 65% of participants' HRmax (60-70 rpm).\n* Progressive muscle relaxation (PMR): The aim of PMR is to achieve enhanced mental relaxation by reducing muscle tension. Participants will attend six 1-h group sessions over the 3-week intervention period, instructed by a trained physical therapist. Six weeks after returning home, the participants will receive a reinforcement letter with information material for remembering the content of the PMR techniques and to reinforce the implementation of the exercises at home.", 'interventionNames': ['Behavioral: Endurance Training', 'Behavioral: Education']}

Interventions:
- {'type': 'BEHAVIORAL', 'name': 'Endurance Training', 'description': 'Treatment in both arms consists of specific endurance exercise modalities (HIIT or ST). Treatments differ in the applied training intensities. Participants in both arms will exercise 3 times per week over a period of 3 weeks on a bicycle ergometer. Exercise sessions will be supervised by a trained physical therapist. Exercise intensity will be heart rate monitored based on the maximum heart rate (HRmax) assessed during the initial cardiopulmonary exercise test. Exercise sessions in both arms will include a warm-up and a cool-down period at low intensity (50% HRmax) for 3 min each.', 'armGroupLabels': ['High-intensity interval training + energy management education', 'Low-intensity training + progressive muscle relaxation']}
- {'type': 'BEHAVIORAL', 'name': 'Education', 'description': 'Treatment in both arms consists of specific energy management education interventions (IEME or PMR). Treatments differ in the applied education approaches. Participants in both arms will exercise 2 times per week over a period of 3 weeks.', 'armGroupLabels': ['High-intensity interval training + energy management education', 'Low-intensity training + progressive muscle relaxation']}

Primary Outcomes:
- {'measure': 'Short-form 36 (SF-36)', 'description': 'Changes of health-related quality of life will be assessed with the SF-36. The SF-36 questionnaire comprises 36 items. Scores range from 0 to 100 with higher values indicating better QoL.', 'timeFrame': '6 months (day 0 - day 183) with time points set after three weeks (day 21) and 4 months (day 122).'}

Please estimate the sample size based on the assumption: 
significance level (α) of 0.025 with Bonferroni correction for multiple comparisons, power (1-β) of 0.8, correlation between baseline and T3 scores of ρ = 0.65, and an 18% dropout rate
Sample size calculation
        The a priori sample size calculation was conducted using G*Power 3.1.9.2 software [44]. It was carried out for the investigation of a between-group difference in the primary endpoint (changes in the HRQoL (PCS and MCS) from baseline to T3) in an analysis of covariance model (ANCOVA).
        Based on our IEME feasibility randomized clinical trial [16] with four months follow-up of HRQoL, we assume a medium between-group effect size of dâ=â0.5 on changes in the primary endpoint HRQoL. Level of significance (Î±) with Bonferroni for multiple comparisons (two primary outcomes) was set at 0.025 and power (1âÎ²) at 0.8. According to Borm et al. 2007 [45], the required sample size for the ANCOVA model was calculated with the formula (1âÏ2)*n. A correlation between participantâs scores at baseline and at T3 of Ïâ=â0.65 was used. The calculation revealed that 90 participants (EG: 45 / CG: 45) would need to be recruited. Based on previous studies that apply similar interventions [16, 22], we have allowed for 18% dropout and plan to recruit 106 participants.