The effect of high-intensity interval training on cognitive function in patients with substance use disorder: Study protocol for a two-armed randomized controlled trial.

Introduction: Substance use disorder (SUD) is characterized by cognitive impairment, especially executive dysfunction. Executive function is recognized as an important determinant of treatment outcome as it is associated with dropout rate, attendance to therapy and potential relapse after treatment termination. Physical activity can have beneficial effects on cognitive function, but there is still a lack of knowledge regarding potential benefits of aerobic exercise for executive function in SUD treatment. The aim of this study is to examine the effect of aerobic high-intensity interval training (HIIT) on cognitive function and the subsequent effect on treatment outcome in patients with SUD. Methods and analysis: This study is a randomized controlled trial, including men and women ≥18 years with diagnosed SUD by ICD-10. The patients will be recruited from the department for inpatient treatment at Blue Cross - Lade Addiction Treatment Center, Trondheim, Norway. Participants will be randomized 1:1 into either HIIT (3x/week) + treatment as usual (TAU), or TAU alone. Study outcomes will be assessed at baseline, after eight weeks of intervention, and at 3- and 12-months follow-up. The primary outcome is to compare the change in executive function (via altered BRIEF-A score, Behavior Rating Inventory of Executive Function-Adult) measured between the two study groups after eight weeks. Secondary outcomes include mapping of cognitive function in different subgroups (e.g. type of substance, age, fitness level), collecting self-reported information about quality of life, craving, sleep quality, etc., as well as assessing compliance to TAU and long-term treatment outcome. Ethics and dissemination: The project was approved by the Regional Ethical Committee and will be performed in accordance with this protocol and the Declaration of Helsinki. Written informed consent will be obtained from all participants prior to inclusion. This project will explore a novel approach to how exercise can be applied in SUD treatment, beyond the well-known effects on physical health. We expect to achieve new knowledge in regard to what extent HIIT can improve cognitive abilities and subsequent treatment outcome in SUD. Trial registration number: https://www.clinicaltrials.gov/NCT05324085.

Cardiopulmonary and muscular effects of different doses of high-intensity physical training in substance use disorder patients: study protocol for a block allocated controlled endurance and strength training trial in an inpatient setting.

INTRODUCTION: Patients with substance use disorder (SUD) have high prevalence of lifestyle-related comorbidities. Physical exercise is known to yield substantial prophylactic impact on disease and premature mortality, and there seems to be an inverse association between physical fitness and adverse health outcomes. High-intensity training is regarded as most effective for improving physical fitness, but less is known concerning the ideal training dose necessary to achieve clinically relevant effects in these patients. The aim of this study is to compare the effect of low-dose and high-dose, high-intensity training, on physical fitness in patients diagnosed with SUD. METHODS AND ANALYSIS: This study will recruit 40 in-patients of mixed genders, aged 18-70 years. Participants will be block allocated to low-dose or high-dose training, encompassing 24 high-intensity interval and maximal strength training sessions (3/week × 8 weeks). After a 10 min warm-up, the low-dose group will perform 1×4 min intervals at ⁓90% of maximal heart rate and 2×4 repetitions strength training at ⁓90% of 1 repetition maximum. The high-dose group will perform 4×4 min intervals at ⁓90% of maximal heart rate and 4×4 repetitions strength training at ⁓90% of 1 repetition maximum. Clinical measurements and physical tests will be conducted at baseline, midway and on completion and a questionnaire on physical activity will be administered at baseline. ETHICS AND DISSEMINATION: This protocol is in accordance with the Standard Protocol Items: Recommendations for Interventional Trials statement. All participants will sign a written informed consent. The Regional Committee of Medical Research Ethics, Norway has approved the study. A study of this kind is warranted, and the results will be published in an open access journal to ensure public access, and presented at national and international conferences. TRIAL REGISTRATION NUMBER: NCT04065334.

Predicting VO2peak from Submaximal- and Peak Exercise Models: The HUNT 3 Fitness Study, Norway.

PURPOSE: Peak oxygen uptake (VO2peak) is seldom assessed in health care settings although being inversely linked to cardiovascular risk and all-cause mortality. The aim of this study was to develop VO2peak prediction models for men and women based on directly measured VO2peak from a large healthy population. METHODS: VO2peak prediction models based on submaximal- and peak performance treadmill work were derived from multiple regression analysis. 4637 healthy men and women aged 20-90 years were included. Data splitting was used to generate validation and cross-validation samples. RESULTS: The accuracy for the peak performance models were 10.5% (SEE = 4.63 mL⋅kg(-1)⋅min(-1)) and 11.5% (SEE = 4.11 mL⋅kg(-1)⋅min(-1)) for men and women, respectively, with 75% and 72% of the variance explained. For the submaximal performance models accuracy were 14.1% (SEE = 6.24 mL⋅kg(-1)⋅min(-1)) and 14.4% (SEE = 5.17 mL⋅kg(-1)⋅min(-1)) for men and women, respectively, with 55% and 56% of the variance explained. The validation and cross-validation samples displayed SEE and variance explained in agreement with the total sample. Cross-classification between measured and predicted VO2peak accurately classified 91% of the participants within the correct or nearest quintile of measured VO2peak. CONCLUSION: Judicious use of the exercise prediction models presented in this study offers valuable information in providing a fairly accurate assessment of VO2peak, which may be beneficial for risk stratification in health care settings.

Cardio-respiratory reference data in 4631 healthy men and women 20-90 years: the HUNT 3 fitness study.

PURPOSE: To provide a large reference material on key cardio-respiratory variables in a healthy population of Norwegian men and women aged 20-90 years. METHODS: Sub maximal and peak levels of cardio-respiratory variables were measured using cardiopulmonary exercise testing during treadmill running. RESULTS: The highest peak ventilation among men (141.9±24.5 L·min-1) and women (92.0±16.5 L·min-1) was observed in the youngest age group (20-29 years, sex differences p<0.001) with an average 7% reduction per decade. The highest tidal volumes were observed in the 30-39 and 40-49 year age groups among men (2.94±0.46 L) and women (2.06±0.32 L) (sex differences p<0.001), with a subsequent average 6% reduction per decade. Ventilatory threshold and respiratory compensation point were observed at approximately 77% and 87% of peak oxygen uptake (VO2peak) among men and women, respectively. The best ventilatory efficiency (EqVCO2Than) was observed in the youngest age group (20-29 years) in both men (26.2±2.8) and woman (27.5±2.7) (sex differences p<0.001) with an average 3% deterioration in ventilatory efficiency per decade. CONCLUSION: This is the largest European reference material of cardio-respiratory variables in healthy men and women aged 20-90 years, establishing normal values for, and associations between key cardio-respiratory parameters. This will be useful in clinical decision making when evaluating cardiopulmonary health in similar populations.

Aerobic capacity reference data in 3816 healthy men and women 20-90 years.

PURPOSE: To provide a large reference material on aerobic fitness and exercise physiology data in a healthy population of Norwegian men and women aged 20-90 years. METHODS: Maximal and sub maximal levels of VO2, heart rate, oxygen pulse, and rating of perceived exertion (Borg scale: 6-20) were measured in 1929 men and 1881 women during treadmill running. RESULTS: The highest VO2max and maximal heart rate among men and women were observed in the youngest age group (20-29 years) and was 54.4±8.4 mL·kg(-1)·min(-1) and 43.0±7.7 mL·kg(-1)·min(-1) (sex differences, p<0.001) and 196±10 beats·min(-1) and 194±9 beats·min(-1) (sex differences, p<0.05), respectively, with a subsequent reduction of approximately 3.5 mL·kg(-1)·min(-1) and 6 beats·min(-1) per decade. The highest oxygen pulses were observed in the 3 youngest age groups (20-29 years, 30-39 years, 40-49 years) among men and women; 22.3 mL·beat(-1)±3.6 and 14.7 mL·beat(-1)±2.7 (sex differences, p<0.001), respectively, with no significant difference between these age groups. After the age of 50 we observed an 8% reduction per decade among both sexes. Borg scores appear to give a good estimate of the relative exercise intensity, although observing a slightly different relationship than reported in previous reference material from small populations. CONCLUSION: This is the largest European reference material of objectively measured parameters of aerobic fitness and exercise-physiology in healthy men and women aged 20-90 years, forming the basis for an easily accessible, valid and understandable tool for improved training prescription in healthy men and women.

Plantar flexion: an effective training for peripheral arterial disease.

This study examined whether a training intervention likely to elicit adaptations in the leg could result in reduced leg pain and increased whole body physical capacity. Twenty-seven peripheral arterial disease (PAD) patients were randomized to either an individual leg plantar flexion training group (TG) training 4 x 4 min intervals at 80% of maximal work rate three times per week for 8 weeks or a control group. The TG significantly increased plantar flexion peak oxygen uptake and power output by 23.5 and 43.9%, respectively. Treadmill peak oxygen uptake (VO(2peak)) significantly increased 12.3% in the TG and was associated with a significant increased time to exhaustion of 20.0% when treadmill walking. Eleven of 14 patients no longer reported leg pain limitations at VO(2peak). No differences in cardiac output measured at VO(2peak), or walking economy were observed. Plantar flexion training was effective in increasing VO(2peak) and walking performance, and may be a useful strategy in treatment of PAD.