Longitudinal affective response to high-intensity interval training and moderate-intensity continuous training in overweight women with polycystic ovary syndrome: A randomised trial

Highlights

• Women with polycystic ovary syndrome (PCOS) report barriers to exercise.

• High-intensity interval training (HIIT) had a positive affective response over time.

• HIIT was more enjoyable than moderate-intensity continuous training (MICT).

• Adherence to both HIIT and MICT was high in women with PCOS.

• HIIT is a promising exercise intervention for overweight women with PCOS.

Abstract

Background

Women with polycystic ovary syndrome (PCOS) experience general and PCOS-specific barriers that limit their engagement with exercise and contribute to high attrition from exercise programs, hindering the potential benefits of exercise to address their increased cardio-metabolic risk. A positive remembered affective response can predict future intentions and adherence to exercise prescription.

Objectives

To compare the longitudinal changes in remembered affect to high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in women with PCOS and to determine whether longitudinal changes in remembered affect are correlated with changes in fitness, body mass index, adherence and exercise enjoyment.

Methods

Physically inactive, overweight women with PCOS were randomly assigned to 12 weeks of either HIIT (n = 15) or MICT (n = 14) (3 sessions per week). Remembered affective valence (Feeling Scale) was collected after each exercise session. Cardiorespiratory fitness (VO_2peak) was assessed at baseline and post-intervention. Exercise enjoyment was assessed post-intervention.

Results

The longitudinal changes in the remembered affect were more positive in the HIIT group compared to MICT (β = 0.017, p = 0.047). HIIT was also considered more enjoyable than MICT (p = 0.002). Adherence was high in both groups (>90%). We found a moderate correlation with longitudinal changes between the remembered affect and change in fitness (r_s = 0.398) and exercise enjoyment (r_s = 0.376) using the combined group, however, these were not statistically significant (p = 0.054 and p = 0.064, respectively).

Conclusions

HIIT demonstrated a more positive longitudinal remembered affective response and greater exercise enjoyment compared to MICT in overweight women with PCOS.

Introduction

Regular exercise is associated with lower all-cause mortality (Zhao et al., 2020), reduced risk of chronic disease (Leskinen et al., 2018; Li & Siegrist, 2012), and reduced incidence of anxiety (Schuch et al., 2019) and depression (Felipe B. Schuch et al., 2018). Compared to healthy women, women with polycystic ovary syndrome (PCOS) are at an increased risk of developing chronic conditions; particularly type 2 diabetes and mental health conditions (Barry et al., 2011; Moran et al., 2010). PCOS is the most common endocrine condition in women of reproductive age (Azziz et al., 2006) and is characterised by hyperandrogenism, menstrual irregularities and polycystic ovary morphology. PCOS is underpinned by reproductive and metabolic abnormalities. Consistent with the World Health Organization physical activity guidelines (Bull et al., 2020), the PCOS specific guidelines recommend a minimum of 150 min of moderate-intensity physical activity or 75 min of vigorous intensity exercise per week (Stepto et al., 2019; Teede et al., 2018). Exercise has been found to improve a range of health outcomes for women with PCOS, including increased insulin sensitivity, fitness, menstrual cycle regulation, hormonal levels and a reduction in the severity of symptoms of anxiety and depression (Almenning et al., 2015; Harrison et al., 2012; Kogure et al., 2020; Patten et al., 2020; Patten et al., 2021; Stener-Victorin et al., 2009).

Despite the health benefits associated with engagement in physical activity, a large proportion of adults in the general population do not meet the minimum physical activity recommendations (Department of Health, 2021). In 2017–2018, only 54.7% of women reported engaging in a minimum of 150 min of physical activity per week, with lack of time consistently reported as the greatest barrier to exercise participation (Department of Health, 2021). Although there is no population scale data, women with PCOS often have high attrition rates to exercise programs and report barriers to exercise including time limitations, low enjoyment and low confidence, all of which are pertinent for women with PCOS (Banting et al., 2014; Conte et al., 2015). In order to increase adherence and compliance to exercise in both the general population and amongst women with PCOS, there is a need to address these barriers. High-intensity interval training (HIIT) has the potential to reduce the time limitation barrier to exercise (Weston et al., 2014), and despite a greater exertion, some studies in cohorts with other chronic conditions have reported equal or greater enjoyment of HIIT as compared to standard moderate-intensity continuous training (MICT) (Astorino & Thum, 2018; Jung et al., 2014; Vella et al., 2017; Wisløff et al., 2007). However, this point is often debated, with some studies suggesting that an acute bout of moderate-intensity exercise is more enjoyable than HIIT (Decker & Ekkekakis, 2017). This debate also exists in regards to affective response, with controversy around which exercise intensity results in a more positive response. Although affect and enjoyment are conceptually related, there are key distinctions. Affective response is based on the pleasure or displeasure of a single ‘in the moment’ experience, whereas enjoyment is based on a global judgement based on an aggregation and evaluation of multiple experiences (Stevens et al., 2020).

There is evidence to suggest that a positively valenced affective response to exercise contributes to adherence to an exercise program (Kwan & Bryan, 2010). Previous studies have shown that a more positively valenced affect during an acute bout of exercise is associated with greater exercise engagement up to 12-months later (Williams et al., 2008). Therefore, the acute affective response has been identified as an important antecedent of physical activity through both automatic and reflective processes (Stevens et al., 2020). Additionally, more positively valenced remembered affect (i.e., recalled affective response to a completed bout/interval of exercise), has also been found to predict future intentions to be physically active and adherence to exercise prescriptions (Kwan et al., 2017). Although the affective response during physical activity and remembered affect are distinct (the former is purely affective whereas the latter is cognitively processed), there is a strong correlation between the affective response during exercise and remembered affect (Hargreaves & Stych, 2013; Zenko et al., 2016). Nevertheless, some have argued that how an affective response to a behaviour is remembered, and not necessarily how it is experienced in the moment, may have a stronger influence on an individual’s motivation to perform that behaviour in the future (Kahneman et al., 1993).

Several mechanisms have been identified that may explain variations in the affective response to exercise between and within individuals over time, including exercise intensity and duration (Ekkekakis et al., 2011), as well as multiple cognitive and contextual factors (Bourke et al., 2021). Other factors that may explain variations in the affective response to physical activity include body mass (Ekkekakis et al., 2010) and physical fitness (Magnan et al., 2013). Similarly, cognitive (Beaumont et al., 2021; Kwan et al., 2011; Kwan et al., 2018) and contextual (Graupensperger et al., 2019) factors may influence variations in the remembered affect following physical activity. Although the affective response to physical activity is variable, few studies have examined longitudinal changes in the affective response to physical activity in people involved in exercise interventions. Examining longitudinal remembered affect may provide valuable information into the likelihood of continued exercise participation. Interventions which are successful in promoting positive affective response will likely lead to increased exercise adherence and, subsequently, to enhanced health outcomes. However, there is no evidence from prospective studies comparing longitudinal changes in remembered affect for volume-matched HIIT and standard MICT in women with PCOS. Therefore, this study aims to examine longitudinal changes in remembered affect in women with PCOS enrolled in an exercise intervention, and to determine whether changes differ between the HIIT and MICT interventions. Additionally, this study aims to determine if longitudinal changes in remembered affect are correlated with critical factors for women with PCOS, including changes in fitness, body mass index (BMI), adherence to the intervention, and exercise enjoyment.