High-intensity Exercise Based on Self-management With Digital Coaching in Patients With Spondyloarthritis: a Randomized Controlled Trial
Phase: NA
Conditions: Axial Spondyloarthritis
Sponsor: Halmstad University

High-intensity training in patients with spondyloarthritis: a randomized controlled trial 
 
June 2022 
 
 
1 (16) 
 
Research protocol 
High-intensity exercise based on self-
management with digital coaching in patients 
with spondyloarthritis: a randomized 
controlled trial  
NCT ID not yet assigned 
 
Authors:  
Åsa Andersson1 ORCID iD  
Anna Torell4 ORCID iD 
M Charlotte Olsson1 ORCID iD 0000-0002-9337-5113, e-mail: charlotte.olsson@hh.se 
Emma Haglund 1,2,3 ORCID iD: 0000-0002-1445-5247, e-mail: emma.haglund@hh.se 
 
1Dept. of Environmental and Biosciences, School of Business, Innovation and Sustainability, 
Halmstad University, Halmstad, Sweden 
2Spenshult Research and Development Centre, Halmstad, Sweden  
3Dept. of Clinical Sciences, Section of Rheumatology, Lund University, Lund, Sweden 
4Dept. of Rehabilitation, Ängelholm hospital, Ängelholm, Sweden 
 
 
 
 

 
2 (16) 
 
Project summary  
 
Background: For people diagnosed with a spondyloarthritis (SpA) e.g. ankylosing spondylitis 
or undifferentiated spondyloarthritis, physical activity and exercise are important components 
in the self-management. Exercise, in addition to physical and mental symptoms related to the 
disease can easily feel overwhelming to exercise, and low adherence may result. By studying 
the effects of high-intensity interval training (HIIT) in comparison with training as usual on 
physiological, inflammatory, and self-reported disease parameters in patients with SpA, we 
intend to further investigate the short-term and longitudinal training effects, and refine the 
knowledge to tailor, coach, and stimulate to self-performed HIIT.  
Objective: The purpose of this study is to investigate the short- (12 weeks) and long-term (12 
months)  effects of high- intensity interval training (HIIT) on physiological, inflammatory, 
and self-reported health parameters in patients with SpA. The aim is also to study the 
adherence to physical activity and exercise recommendations.  
Design: A randomized controlled trial (RCT) design.  
Participants: One hundred adults with a confirmed axial SpA from rheumatology clinics in 
southern Sweden will be recruited and randomized into two groups, the intervention group 
and the control group.  
Intervention: Three high-intensity training sessions per week for three months, of which two 
interval sessions, with coaching both from a clinical physiotherapist and digital devices 
(watch and app) followed by nine months with sporadic coaching. The control group will go 
on with exercise as usual. 
Primary outcome: Self-reported disease activity, inflammatory biomarkers (acute phase 
proteins). 
Secondary outcomes: Physical fitness (aerobic capacity (VO2max), blood pressure, grep 
strength), body composition and self-reported physical function, health status, well-being, 
pain, fatigue, adherence to physical activity and exercise recommendations, and confidence in 
one's own ability to manage pain, symptoms and high-intensity exercise, and additional serum 
biomarkers (listed in the Methodology section). 
 
 

 
3 (16) 
 
Project description:  
 
Rationale  
An increasing number of scientific reports are stating a role for exercise as medicine in 
different diseases, e.g., inflammatory musculoskeletal disorders. The importance of 
physical activity, exercise and rehabilitation as part of disease- and self-management 
have also been emphasized by both WHO and by the public health authority in Sweden 
(1, 2). 
SpA is an umbrella term for a group of inflammatory diseases with a prevalence that 
varies between 0.2% - 1.6% globally (3). SpA can be divided into two forms; axial SpA 
characterized by inflammation in the spine and pelvic joints, and in peripheral SpA 
characterized by inflammation in peripheral joints, entesites and dactylites (4-6). The 
group axial SpA includes both patients with X-ray changes in the sacroiliac joints or 
spine (radiographic axial SpA) but also patients where these X-ray-verified changes have 
not yet been detected (non-radiographic axial SpA) (6). Recommended treatment 
consists of a combination of pharmacological and non-pharmacological interventions (7, 
8). The non-pharmacological treatment includes physiotherapy with disease counselling 
and specific training (7, 9-11). There is an increased risk of comorbidity such as 
cardiovascular disease, obesity, depression and osteoporosis in patients with axSpA 
compared to the healthy population (12). The risk of several of the comorbidities that 
occur is considered to be reduced through an increased degree of physical activity (13-
15). The increased cardiovascular risk is considered multifactorial but is partly explained 
by the chronic systemic inflammation and a low level of physical activity in the 
individuals living with the disease (11, 16).  
The effects of HIIT with respect to inflammatory biomarkers are poorly studied in 
individuals with rheumatic diseases such as rheumatoid arthritis and SpA. Also, proteins 
secreted by muscle cells during physical activity, myokines, and their suggested effect to 
counteract the inflammatory process, need to be further studied (17-19). HIIT is believed 
to be able to affect both the disease outcome and the increased risk of cardiovascular 
morbidity (15), but more studies are needed to obtain sufficient evidence along with new 
biomarkers recently found to affect inflammation that can be implemented in a general 
maintenance of the individuals’ systemic inflammatory status (20). 

 
4 (16) 
 
In the general population, the greatest positive effect is seen on cardiovascular disease 
and its risk factors during cardio training at a higher intensity (21-23). Studies show that 
individuals with SpA can exercise at a higher intensity level without exacerbating 
disease activity and that HIIT can reduce inflammation and reduce the cardiovascular 
risk factors for individuals with SpA (13, 15, 19, 24).  
Despite the overwhelming evidence that exercise will help in the disease management, 
individuals with the disease still find it difficult to make exercise a sustainable routine in 
their lives. Previous studies have shown that when a coach-led intervention ends, it is 
common with a large drop-out rate and that compliance decreases (19, 22). Our habits 
are deeply rooted, and a determined effort is needed to succeed with a behavior change, 
such as getting started with regular training or changing the type of a previously 
accustomed training routine (e.g., regarding intensity). Changing a behavior should 
therefore take place gradually and over a long period of time to have the best conditions 
to become permanent. With the help of repetition of the current training approach, partly 
under the guidance of a coach, partly through self-performed training sessions, the 
foundation is laid for the new training behavior to be maintained over time (25, 26). A 
person-centered approach with the opportunity to choose activity, and be able to vary 
activity and training sessions have proven to be important factors that increase 
compliance with HIIT (27). High-intensity training in self-selected activity performed as 
self-performed training outside the health care has been shown to work well for patients 
with cardiovascular disease (28, 29). At follow-up one year after the end of the training 
intervention, there was no significant difference in compliance between those who 
participated in coach-led high-intensity training and those who self-performed the 
training (30). Active coaching, registration of heart rate level during training and 
estimation of perceived effort have all been shown to be important to achieve the right 
training intensity (21, 22). Telehealth, in which health coaching is provided via 
telecommunications and other virtual communication devises outside traditional health 
care, is considered an important part of modern care, among other things, to encourage 
an increased degree of physical activity, exercise and behavior change. However, the 
effects of this type of intervention are still incompletely studied (31, 32). HIIT is thought 
to affect both the disease activity and factors associated with the risk of cardiovascular 
disease that exists in individuals with SpA, but the research is still insufficient.  
The effects of HIIT on physical, inflammatory, and self-reported health parameters needs 

 
5 (16) 
 
to be further studied. The knowledge is also scarce on how to tailor the high-intensity 
training as a part of the self-management for individuals with SpA, with the aim to 
maintain regular exercise routines and sustainable health over time. 
 
 
Objectives  
 
The purpose of this study is to investigate the short- (12 weeks) and long-term (12 months) 
effects of self-performed high-intensity interval training (HIIT) on physiological, 
inflammatory, and self-reported health parameters in patients with SpA. The aim is also to 
study the adherence to the physical activity and exercise recommendations. 
The primary hypothesis in this study is that there will be significant differences between the 
intervention group and the control group concerning self-reported disease activity, in some of 
the inflammatory biomarkers (acute phase proteins and pro-inflammatory cytokines), and in 
adherence to vigorous intensity performed physical activity and exercise both in the short and 
long term. 
The secondary hypothesis is that there will be significant differences between patients in the 
intervention group and the control group regarding physiological health (aerobic capacity, 
blood pressure, grip strength, body composition), and self-reported health (physical function, 
health status, well-being, pain, fatigue, inactivity), and in the confidence in one’s own ability 
to manage pain, symptoms, and high-intensity training, after both three- and twelve-months 
follow-ups.  
 
 
 

 
6 (16) 
 
Methodology 
 
Study design and procedure 
This study will be performed as a randomized controlled trial (RCT) study and will be 
adhering to the CONSORT statement (33). The results of a three-months intervention with 
high-intensity training, followed by nine months with customized coaching where the 
intervention group will be motivated and strengthened in their own confidence to continue 
training regularly at high-intensity levels, will be compared to the control group for primary- 
and secondary outcomes. The control group will continue with exercise as usual based on the 
treatment recommendations for patients with SpA (7, 10, 11). 
Participants will be randomly assigned into intervention- and control groups. Simple 
randomization will be used for equal group allocation at three different rheumatology clinics 
in southern Sweden. The patients will choose a sealed note in which one of the words 
“intervention” or “control” is written, when the baseline assessment is completed at the first 
measurement occasion. The patients in the intervention group will then perform an estimation 
of her/his maximal heart rate (MHR) on a stationary bicycle and effort on the ratings of 
perceived exertion (RPE)-scale (34) to be confident at recognizing the level of effort at the 
appropriate heart rate (HR) to reach an intensity of at least 17 on RPE during the following 
HIIT sessions. After this initial assessment, the clinical coach will set up individual training 
zones (for intervals and active rest) and the focus thereafter is for the patients to continue the 
intervention in self-selected activities based on a standardized training setup. After 1, 2 and 
then again at 7 weeks, the patients will be offered follow-ups with coach-led HIIT and the 
individual HR zones will be readjusted if needed. 
The patients in the control group will not receive any standardized exercise intervention 
but will be wearing a heart rate monitor watch during the year. The baseline tests 
include both patients in the experimental and control groups. Baseline tests will include 
physiological tests, body composition, blood tests, self-reported questionnaire including 
different health variables, collected during one visit. After 12 weeks of intervention, and 
after one year the same assessment will be made. 
Participants 
The patients will be recruited from rheumatological clinics in southern Sweden, through 
invitation via personal contact by the physiotherapist at the clinic. 

 
7 (16) 
 
A clinical physiotherapist at each centre will identify eligible patients form their unit 
and, after checking the inclusion criteria in the medical record, contact the patients to 
further screen for cardiovascular or other comorbidities contraindicated for high-
intensity training. After showing interest in participating, they will receive oral and 
written information (appendix 1). An informed consent will be signed by all included 
patients before the data collection will start. 
Inclusion Criteria: 
Aged 18-65. Axial SpA (ICD10 diagnosis of M45, M46.0, M46.1, M46.8 and M46.9). The 
patients should meet the general recommendations for physical activity, at least 150 minutes 
of moderate-intensity aerobic physical activity throughout the week or doing at least 75 
minutes of vigorous-intensity aerobic physical activity throughout the week or an equivalent 
combination of moderate - and vigorous-intensity activity (35). 
Exclusion Criteria: 
Changed TNF and anti-inflammatory medication the previous three months, established, or 
symptoms of, cardiovascular disease or other comorbidities that make high-intensity training 
inappropriate. Lastly, those who already perform sufficient high-intensity interval training on 
a regular basis will be excluded from this study. At the initial visit the physiotherapist will 
start by measuring the chest thumb electrocardiography (ECG). In the event of two repeated 
deviating results regarding the ECG, the patients will be referred to the health centre for 
further investigation before any inclusion. 
Outcome Measures 
Primary outcome measures: (1) Self-reported disease activity, and (2) inflammatory 
biomarkers (acute phase proteins). 
(1) Self-reported disease activity 
The disease-specific Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (36) and 
Ankylosing Spondylitis Disease Activity Score with C‐reactive protein (ASDAS-CRP) (8) 
will be used to assess self-reported disease activity. BASDAI consists of six questions on 
fatigue, pain, tenderness, and morning stiffness. numeric questions (range 0-10). The final 
score is estimated by calculating the mean. ASDAS-CRP consists of four questions on pain in 
neck, back, and hip, morning stiffness, well-being, and pain/stiffness in other joints in 
addition to blood test of CRP. The final score is estimated using a formula (37) . 
  

 
8 (16) 
 
(2) Inflammatory biomarkers (acute phase proteins) 
A total of approximately 4 ml blood will be drawn at baseline, after 12 weeks and after one 
year. To study C-reactive protein (CRP), Pentraxin-related protein (PTX3), and serum 
amyloid A1 (in µg/ml) the enzyme-linked immunosorbent assay (ELISA) will be used.  
Secondary outcomes: Physical fitness (aerobic capacity VO2max, blood pressure, grip 
strength), body composition and self-reported variables such as physical function, health 
status, well-being, pain, fatigue, adherence to physical activity and exercise recommendations 
and confidence in one's own ability to manage pain, symptoms, and high-intensity exercise. 
Venous blood samples will be drawn to study lipoproteins, cytokines, myokines, and markers 
for bone remodulation. 
Physical fitness 
Aerobic capacity (VO2max) will be measured according to Åstrand with a submaximal cycle 
ergometer test on an indoor stationary bicycle (Monark 828E, Monark Exercise AB, Vansbro, 
Sweden) (38). Aerobic capacity will be presented relative to body weight and expressed as the 
total amount of oxygen metabolized per minute per kilogram of body weight (mL/kg/min) 
(39). Blood pressure will be measured. with an automatic blood pressure monitor (Omron M3, 
Omron Healthcare Co, Mukō, Japan), and a hand dynamometer (KERN Sohn GmbH, 
Balingen, Germany) will measure the maximum hand grip strength (kg) as another indicator 
of general body strength (40). 
Body composition 
The hight and weight of the participants will be measured, and BMI calculated. Proportion of 
fat and visceral fat area (VFA) will be assessed by bioelectrical impedance analysis (Inbody 
770®, Seoul, Korea) (41). 
Self-reported variables 
Physical function will be measured with the Bath Ankylosing Spondylitis Indices for function 
(BASFI) (42). The BASFI consists of ten questions on body function, activity and 
participation and environmental factors. The final score will be estimated by calculating the 
mean.  
Health status will be measured with the generic questionnaire EuroQol-5 domain (EQ-5D) 
consisting of five questions covering mobility, self-care, usual activity, pain/discomfort, and 
anxiety/depression. The total score range from 0-1 (no health to full health) (43).  

 
9 (16) 
 
Well-being will be measured with the Assessment of SpondyloArthritis International Society 
Health Index /ASAS-HI), consisting of 17 statements (yes/no) on pain, emotional functions, 
sleep, sexual functions, mobility, self-care and participation (44). The total score ranges from 
0-17.  
Pain will be measured with a pain mannequin, with 18 predefined regions (pain regions) 
where participants mark their painful areas on the pain figure if they have any They will also 
respond to questions about pain intensity (numeric rating scale, NRS 0-10, best to worst), 
duration and diurnal variation of pain. (45).  
Fatigue will be measured with the Fatigue Severity Scale (FSS) (46) and on a numerical rating 
scale from 0-10 (no fatigue-worst possible fatigue) (47). FSS consists of nine statements of 
the consequences of fatigue. The total score range from 9-63 (best-worst).  
Adherence to physical activity and exercise recommendations will be objectively measured 
through the heart rate monitor watch in average minutes of moderate/vigorous level of 
physical activity per week. Self-reported adherence to physical activity and exercise 
recommendations will be collected through three validated questions including information on 
intensity, frequency, and duration (1).  
Confidence in one's own ability to manage pain, symptoms, and high-intensity exercise will 
be measured with the Arthritis Self-Efficacy Scale (ASES) for pain and symptoms (48), and 
the Swedish Exercise Self-Efficacy Scale (S-ESES) (49). The ASES subscale for pain has five 
items and the subscale for symptoms has six items. The total scores range from 10-100 (low 
to high self-efficacy). The S-ESES consists of 10 statements where each question has four 
response options, from not at all safe to completely confident. The total score ranges from 10-
40  
Lipoproteins, cytokines, myokines, and markers for bone remodulation 
Pro-inflammatory cytokines and chemokines (TNF-α, IL-6, IL17a, IL-18, IL-21, IL-23, 
CXCL10, in pg/ml); additional inflammation-related proteins (VEGF-A, IL-1Ra, IL-8, MIP-
1a, MIP-1β in pg/ml, serum calprotectin (in µg/ml), albumin for CRP/albumin ratio in mg/ml; 
myokines (irisin, BDNF in ng/ml); bone and cartilage proteins (DKK-1 in pg/ml, osteocalcin, 
sclerostin, osteopontin in ng/ml, FGF-23 in pg/ml, BMP- 7, MMP-3 in ng/ml); liver-derived 
protein (FGF-21) in ng/ml); and plasma lipoproteins (ApoB and ApoA1) in g/L will be 
analyzed. Protein biomarkers will be measured on a Luminex MAGPIX® system (Luminex 
Corporation, Austin, TX) or with ELISA (Microplate reader, Molecular Devices), while 

 
10 (16) 
 
plasma samples will be sent to the hospital chemistry lab for analysis according to the current 
laboratory standards (lipoproteins). The samples to be analyzed with ELISA and Luminex 
will be stored at -80°C in a biobank at FoU Spenshult, Halmstad (R&D-Spenshult) and the 
analyzes will be performed in the Rydberg Laboratory at Halmstad University.  
Intervention 
High-intensity interval training 
The patients in the intervention group will be instructed to perform two HIIT/week and one 
further training session at moderate or high-intensity of their own choice every week mostly 
on their own for 12 weeks. Structured coaching will be given by a physiotherapist with 
support of text messages and a HR feedback from a fitness watch (Polar Ignite, Polar Electro 
Oy, Kempele, Finland) that the patient will use. The approach is based on a person-centred 
care approach with self-selected activity that engages large muscle groups, such as cycling, 
Nordic walking, running, swimming, rowing, cross-training. During the first 12 weeks, coach-
led sessions are offered on at least three occasions, during week 1, 2 and 7 with the aim of 
guiding the patients to the right intensity of training during the HIIT sessions. The intensity 
will be individually based on the patient’s MHR and physical capacity. If necessary, 
additional coach-led sessions will be offered during the first 12 weeks. After the 12 initial 
weeks, the intervention continues for another nine months with customized coaching where 
the patients will be motivated and strengthen in their own confidence to continue with HIIT 
sessions. During this time, the participants will go on and register the training sessions with 
the fitness watch, and they will be contacted once a month by their coach for guidance on 
regular training. 
 
The intervention begins with a coach-led interval session during week 1 consisting of 4x4 min 
intervals with 3 minutes active rest (at 50-70% of MHR) between each interval. The first 
session will be performed on a stationary bicycle. The session will start with a warm-up to a 
heart rate of 60-70% of MHR, afterwards the load will be increased to 85% of MHR in the 
interval with the intention to reach 90% at some point during each interval. Perceived exertion 
will be assessed with the RPE scale and the goal is to reach at least RPE 17 during the 
intervals (50). The session will end with a cool down at <60% MHR. The patient will be able 
to choose between different interval sessions, but the total time for the intervals in each 
session should be 15 minutes. In addition to the two HIIT session, the patient will be 

 
11 (16) 
 
instructed to perform one further high-intensity training each week at a HR of at least 75% of 
MHR or at RPE 14. At least one rest day should be planned in between each session.  
 
The continuous monitoring of HR and individual coaching will be based on data available 
through the fitness watch. The different sessions of high-intensity training will be registered 
by the patients using their fitness watch and a web-based coaching platform. The coaching 
physiotherapist will log in as a coach and be able to follow the training sessions digitally 
every week. During the first four weeks, the patients will be contacted once a week by e.g., 
phone by coaches at the clinic. After week 4, the follow-up of each patient will be based on 
their own wishes, but at least once/month. Three text messages/week will be sent to the 
patients in the intervention group during the initial 12 weeks with a reminder to stay active.  
Control group 
The patients in the control group continues with their regular physical activity and exercise 
routines as before, i.e., they should keep following the general recommendations for physical 
activity and exercise (51). The control group will be instructed to use the fitness watch and 
log their training on the web-based coaching platform in the same way as the intervention 
group, during their physical activity and exercise, to enable comparisons at the end of the 
intervention.  
Data management and analysis  
Data analysis will be performed using Microsoft Excel and IBM SPSS (IBM SPSS Statistics 
for Windows, Version 24.0. IBM, Armonk, New York, USA). The level of significance is set 
to p<0.05. Demographic data will be summarised using descriptive statistics. Depending on if 
the data is normally distributed or not, appropriate statistical method will be used based on 
which data (categorical, ordinal, interval) that will be analyzed. If normally distributed, the 
main outcomes will be analyzed with two-way ANOVA. To find a minimum difference 
between the groups according to self-reported disease activity (15), a sample size calculation 
of 50 patients for two subgroups, approximately 100 participants, will be needed to obtain a 
power of 80% at a significance level of 5%. 
Ethical and social considerations 
The study will be accomplished in the terms of the Declaration of Helsinki (52). The 
Swedish Ethical Review Authority approved the study (2019-04155, 2022-03114-02). 
The included patients will receive oral and written information of the physical tests, the 

 
12 (16) 
 
blood samples, the questionnaires, and the intervention before the start of data sampling. 
All patients will give the permission to participate by signing an informed consent before 
any data is collected. A screening will be performed before inclusion, through questions 
about comorbidities (lung disease, cardiovascular disease or other disease other than 
SpA). An ECG will be taken at the initial baseline visit to rule out atrial fibrillation and 
the blood pressure will be measured to check for high blood pressure. If no exclusion 
criteria will be detected in these assessments the anthropometric and physiological tests 
(body composition, grip strength, submaximal cycling test) will be performed by trained 
test leaders. During these tests, the prevailing guidelines, and regulations for testing, 
handling of data, including the personal data will be followed. Blood samples will be 
drawn by trained healthcare professionals who follow the regulations and requirements 
for reporting and registration that exist regarding blood sampling and analysis. The 
amount of blood (20 ml per occasion) is not considered to pose an increased risk to the 
patients. The participants will be informed that the high-intensity training included in the 
intervention does not comprise greater risks than if they train high-intensity in other 
settings. They will be informed that HIIT can cause temporary dizziness and high blood 
pressure and that due to glycogen deficiency in the body, in very rare cases, it can cause 
temporary unconsciousness. They will also be informed about the safety that has been 
established, where the test leaders will be well acquainted with emergency care during the 
baseline MHR test. Furthermore, defibrillators are available in connection with the 
premises that will be used in case of an incident. The patients will be instructed to avoid 
food and drink two hours before the baseline visit, prior to measurement of the body 
composition and taking the blood tests. When a MHR test will be done (patients assigned 
to intervention group), we will offer a sweet beverage before this test. Furthermore, 
patients are instructed to abstain from tobacco 30 minutes before the tests and not to 
exercise on high-intensity level the evening before the tests. The participants will be well 
informed about their volunteering, and that they can choose to end their participation at 
any time, without it affecting future contact with the coach, test leader or care unit.  
All collected study-specific data (questionnaires, physical assessments, blood analysis) 
will be managed confidential and the patients’ personal data will be replaced by codes, 
meaning no data can be linked to any identifiable individual. The researcher involved in 
the data collection will be the only one who has access to the code key. All data will be 
entered manually into Excel by responsible researchers. The results from the routine 

 
13 (16) 
 
blood samples will be entered into the medical record in accordance guidelines and the 
Patient Data Act and data will then retrieved from there to the Excel files. During the 
project, data will be stored in such a way that no unauthorized individuals will have 
access to it. Only researchers in the project will have access to the coded data for the 
analysis and the results will be presented at group levels. The freezers, in which saved 
blood samples will be stored, are locked, and located in alarmed rooms at the biobank and 
at the university.  
After the analyses are finished the collected data will be stored on a security-protected 
server at Halmstad University, and the blood samples will be stored in a biobank at FoU 
Spenshult. After finished the sampling, the key code will be stored in a safe at Halmstad 
University and only the project manager will have access. 
Gender issues 
Research is lacking regarding effects of high-intensity interval training. Thus, in this project 
we will study both women and men together, for the intention to provide insights on the effect 
of high-intensity exercise on physiological, inflammatory, and self-reported health parameters 
in patients with SpA. Due to the limited number of participants, there will be no opportunity 
to study gender specific issues.  
 
Trial registration number:  ClinicalTrials.gov xxx 
Timetable 
2022– identification/inclusion of patients and start of the intervention. One center at a time will 
include patients  
2023-2025 – ending the one-year intervention 
2023-2024 – starting analyses of short-term effects  
2025-2026 – analyses of long-term effects and reporting the results 
 

 
14 (16) 
 
References 
1. 
Sweden TPHAi. Physical activity https://www.folkhalsomyndigheten.se/the-public-
health-agency-of-sweden/living-conditions-and-lifestyle/physical-activity/2020 [ 
2. 
Organization WH. Rehabilitation 2020 Initiative 
https://www.who.int/initiatives/rehabilitation-20302017 [ 
3. 
Stolwijk C, van Onna M, Boonen A, van Tubergen A. Global Prevalence of 
Spondyloarthritis: A Systematic Review and Meta-Regression Analysis. Arthritis Care Res 
(Hoboken). 2016;68(9):1320-31. 
4. 
Rudwaleit M, van der Heijde D, Landewe R, Listing J, Akkoc N, Brandt J, et al. The 
development of Assessment of SpondyloArthritis international Society classification criteria for axial 
spondyloarthritis (part II): validation and final selection. Ann Rheum Dis. 2009;68(6):777-83. 
5. 
Rudwaleit M, van der Heijde D, Landewe R, Akkoc N, Brandt J, Chou CT, et al. The 
Assessment of SpondyloArthritis international Society classification criteria for peripheral 
spondyloarthritis and for spondyloarthritis in general. Ann Rheum Dis. 2010. 
6. 
Sieper J, Poddubnyy D. Axial spondyloarthritis. Lancet. 2017;390(10089):73-84. 
7. 
Rausch Osthoff AK, Niedermann K, Braun J, Adams J, Brodin N, Dagfinrud H, et al. 
2018 EULAR recommendations for physical activity in people with inflammatory arthritis and 
osteoarthritis. Ann Rheum Dis. 2018;77(9):1251-60. 
8. 
van der Heijde D, Ramiro S, Landewe R, Baraliakos X, Van den Bosch F, Sepriano A, 
et al. 2016 update of the ASAS-EULAR management recommendations for axial spondyloarthritis. 
Ann Rheum Dis. 2017;76(6):978-91. 
9. 
Dagfinrud H, Kjeken I, Mowinckel P, Hagen KB, Kvien TK. Impact of functional 
impairment in ankylosing spondylitis: impairment, activity limitation, and participation restrictions. J 
Rheumatol. 2005;32(3):516-23. 
10. 
van den Berg R, Baraliakos X, Braun J, van der Heijde D. First update of the current 
evidence for the management of ankylosing spondylitis with non-pharmacological treatment and non-
biologic drugs: a systematic literature review for the ASAS/EULAR management recommendations in 
ankylosing spondylitis. Rheumatology (Oxford). 2012;51(8):1388-96. 
11. 
Martey C, Sengupta R. Physical therapy in axial spondyloarthritis: guidelines, evidence 
and clinical practice. Curr Opin Rheumatol. 2020;32(4):365-70. 
12. 
Zhao SS, Robertson S, Reich T, Harrison NL, Moots RJ, Goodson NJ. Prevalence and 
impact of comorbidities in axial spondyloarthritis: systematic review and meta-analysis. . 
Rheumatology (Oxford). 2020;59:47–57. 
13. 
Sveaas SH, Berg IJ, Provan SA, Semb AG, Hagen KB, Vollestad N, et al. Efficacy of 
high intensity exercise on disease activity and cardiovascular risk in active axial spondyloarthritis: a 
randomized controlled pilot study. PLoS One. 2014;9(9):e108688. 
14. 
Verhoeven F, Guillot X, Prati C, Mougin F, Tordi N, Demougeot C, et al. Aerobic 
exercise for axial spondyloarthritis - its effects on disease activity and function as compared to 
standard physiotherapy: A systematic review and meta-analysis. International journal of rheumatic 
diseases. 2018. 
15. 
Sveaas SH, Bilberg A, Berg IJ, Provan SA, Rollefstad S, Semb AG, et al. High 
intensity exercise for 3 months reduces disease activity in axial spondyloarthritis (axSpA): a 
multicentre randomised trial of 100 patients. Br J Sports Med. 2019. 
16. 
Toussirot E. The Risk of Cardiovascular Diseases in Axial Spondyloarthritis. Current 
Insights. Front Med (Lausanne). 2021;8:782150. 
17. 
Díaz BB, González DA, Gannar F, Pérez MCR, de León AC. Myokines, physical 
activity, insulin resistance and autoimmune diseases. Immunology Letters 2018;203:1-5. 
18. 
Lombard G, Ziemann E, Banfi G. Physical Activity and Bone Health: What Is the Role 
of Immune System? A Narrative Review of the Third Way. Front Endocrinol (Lausanne). 2019;10: 60. 
19. 
Thomsen RS, Nilsen TIL, Haugeberg G, Bye A, Kavanaugh A, Hoff M. Impact of 
High-Intensity Interval Training on Disease Activity and Disease in Patients With Psoriatic Arthritis: 
A Randomized Controlled Trial. Arthritis Care Res (Hoboken). 2019;71(4):530-7. 
20. 
Brown MA, Li Z, Cao KL. Biomarker development for axial spondyloarthritis. Nat Rev 
Rheumatol. 2020;16(8):448-63. 

 
15 (16) 
 
21. 
Karlsen T, Aamot IL, Haykowsky M, Rognmo O. High Intensity Interval Training for 
Maximizing Health Outcomes. Prog Cardiovasc Dis. 2017;60(1):67-77. 
22. 
Ito S. High-intensity interval training for health benefits and care of cardiac diseases - 
The key to an efficient exercise protocol. World journal of cardiology. 2019;11(7):171-88. 
23. 
Martland RM, V., Gaughran F, Stubbs B. Can high-intensity interval trainingimprove 
physical and mental health outcomes? A meta-review of 33 systematic reviews across lifespan. Journal 
of Sports scienses 2020;38(4). 
24. 
Niedermann K, Sidelnikov E, Muggli C, Dagfinrud H, Hermann M, Tamborrini G, et 
al. Effect of cardiovascular training on fitness and perceived disease activity in people with ankylosing 
spondylitis. Arthritis Care Res (Hoboken). 2013;65(11):1844-52. 
25. 
Bandura A. Organisational applications of social cognitive theory. Australian Journal of 
management. 1988;13(2):275-302. 
26. 
Young MD, Plotnikoff RC, Collins CE, Callister R, Morgan PJ. Social cognitive theory 
and physical activity: a systematic review and meta-analysis. Obes Rev. 2014;15(12):983-95. 
27. 
Taylor JL, Holland DJ, Keating SE, Bonikowske AR, Coombes JS. Adherence to High-
Intensity Interval Training in Cardiac Rehabilitation: A REVIEW AND RECOMMENDATIONS. J 
Cardiopulm Rehabil Prev. 2021;41(2):61-77. 
28. 
Moholdt T, Bekken Vold M, Grimsmo J, Slordahl SA, Wisloff U. Home-based aerobic 
interval training improves peak oxygen uptake equal to residential cardiac rehabilitation: a 
randomized, controlled trial. PLoS One. 2012;7(7):e41199. 
29. 
Aamot IL, Forbord SH, Gustad K, Lockra V, Stensen A, Berg AT, et al. Home-based 
versus hospital-based high-intensity interval training in cardiac rehabilitation: a randomized study. Eur 
J Prev Cardiol. 2014;21(9):1070-8. 
30. 
Aamot IL, Karlsen T, Dalen H, Stoylen A. Long-term Exercise Adherence After High-
intensity Interval Training in Cardiac Rehabilitation: A Randomized Study. Physiotherapy research 
international : the journal for researchers and clinicians in physical therapy. 2016;21(1):54-64. 
31. 
Peretti A, Amenta F, Tayebati SK, Nittari G, Mahdi SS. Telerehabilitation: Review of 
the State-of-the-Art and Areas of Application. JMIR Rehabil Assist Technol. 2017;4(2):e7. 
32. 
de Thurah A, Bremander A, Primdahl J. High-quality RMD rehabilitation and 
telehealth: Evidence and clinical practice. Best Pract Res Clin Rheumatol. 2020:101513. 
33. 
Statement C. http://www.consort-statement.org/consort-20102010. 
34. 
Borg G. Borg's perceived exertion and pain scales. Human kinetics. 1998. 
35. 
WHO. WHO guidelines on physical activity and sedentary behaviour: . Licence CC 
BY-NC-SA 3.0 IGO: World Health Organization; 2020. 
36. 
Garrett S, Jenkinson T, Kennedy LG, Whitelock H, Gaisford P, Calin A. A new 
approach to defining disease status in ankylosing spondylitis: the Bath Ankylosing Spondylitis Disease 
Activity Index. J Rheumatol. 1994;21(12):2286-91. 
37. 
Machado PM, Landewe R, Heijde DV, Assessment of SpondyloArthritis international 
S. Ankylosing Spondylitis Disease Activity Score (ASDAS): 2018 update of the nomenclature for 
disease activity states. Ann Rheum Dis. 2018;77(10):1539-40. 
38. 
Åstrand I. Aerobic work capacity in men and women with special reference to age. 
Acta Physiol Scand Suppl. 1960;49(169):1-92. 
39. 
Åstrand P-O, Ryhming I. A nomogram for calculation of aerobic capacity (physical 
fitness) from pulse rate during submaximal work. Journal of applied physiology. 1954;7.2:218-21. 
40. 
Nilsen T, Hermann M, Eriksen CS, Dagfinrud H, Mowinckel P, Kjeken I. Grip force 
and pinch grip in an adult population: reference values and factors associated with grip force. Scand J 
Occup Ther. 2012;19(3):288-96. 
41. 
Lahav Y, Goldstein N, Gepner Y. Comparison of body composition assessment across 
body mass index categories by two multifrequency bioelectrical impedance analysis devices and dual-
energy X-ray absorptiometry in clinical settings. Eur J Clin Nutr. 2021;75(8):1275-82. 
42. 
Calin A, Garrett S, Whitelock H, Kennedy LG, O'Hea J, Mallorie P, et al. A new 
approach to defining functional ability in ankylosing spondylitis: the development of the Bath 
Ankylosing Spondylitis Functional Index. J Rheumatol. 1994;21(12):2281-5. 
43. 
TheEuroQulGroup. EuroQol - a new facility for the measurement of health-Related 
Quality of Life. 1990;16(3):199-208. 

 
16 (16) 
 
44. 
Alonso-Castro S, Pardo E, Charca L, Pino M, Fernandez S, Alperi M, et al. 
Performance of the ASAS Health Index for the Evaluation of Spondyloarthritis in Daily Practice. J 
Rheumatol. 2020;47(10):1483-9. 
45. 
Bergman S, Herrstrom P, Hogstrom K, Petersson IF, Svensson B, Jacobsson LT. 
Chronic musculoskeletal pain, prevalence rates, and sociodemographic associations in a Swedish 
population study. J Rheumatol. 2001;28(6):1369-77. 
46. 
Krupp LB, LaRocca NG, Muir-Nash J, Steinberg AD. The fatigue severity scale. 
Application to patients with multiple sclerosis and systemic lupus erythematosus. Arch Neurol. 
1989;46(10):1121-3. 
47. 
Gladman D, Nash P, Goto H, Birt JA, Lin CY, Orbai AM, et al. Fatigue numeric rating 
scale validity, discrimination and responder definition in patients with psoriatic arthritis. RMD Open. 
2020;6(1). 
48. 
Lorig K, Chastain RL, Ung E, Shoor S, Holman HR. Development and evaluation of a 
scale to measure perceived self-efficacy in people with arthritis. Arthritis Rheum. 1989;32(1):37-44. 
49. 
Ahlstrom I, Hellstrom K, Emtner M, Anens E. Reliability of the Swedish version of the 
Exercise Self-Efficacy Scale (S-ESES): a test-retest study in adults with neurological disease. 
Physiotherapy theory and practice. 2015;31(3):194-9. 
50. 
Taylor JL, Holland DJ, Spathis JG, Beetham KS, Wisloff U, Keating SE, et al. 
Guidelines for the delivery and monitoring of high intensity interval training in clinical populations. 
Prog Cardiovasc Dis. 2019;62(2):140-6. 
51. 
WHO WHO. Global recommendations on physical activity for health. In: Organization 
WH, editor. Geneva, Switzerland: WHO Press; 2010. 
52. 
Association WM. Declaration of Helsinki - Ethical principles for medical research 
involving human subjects. In: association. Wm, editor. https://www.wma.net/policies-post/wma-
declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects/1964.2013.