Background The time of day that exercise is performed may affect adherence and influence physiological outcomes, due to circadian rhythms and nutrition-exercise interactions. For example, exercise performed in the evening may be associated with reduced perception of effort (Maraki et al., 2005) and may improve glycaemic control more than morning exercise (Savikj et al., 2019). Also, pre-exercise feeding is known to affect metabolism, with morning exercise performed before, compared to after a meal, shown to improve insulin sensitivity to a greater extent (Van Proeyen et al., 2010; Edinburgh et al., 2020). Before designing exercise interventions to improve health outcomes, we first need to understand when people choose to exercise and in what proximity from the previous meal. Therefore, this study surveyed exercise timing behaviours, preferences, and opportunities, to inform future exercise interventions to improve health. Methods An online survey was completed by 512 adults to assess typical times of day that exercise is performed and proximity of exercise to the previous meal. Due to the timing of release of this survey, responses to these questions were assessed for both before, and during COVID-19 social distancing measures. In addition, preference and opportunity-based determinants of exercise timing were assessed. Descriptive statistics and between-group comparisons were calculated, and associations between categorical variables were examined using Pearson’s chi-squared analyses. Results The most common time to exercise was the early evening (40.4%) during the week and the morning (57.6%) during the weekend. During social distancing, morning was the most common exercise time during the week (32.0%) and weekend (49.2%). Exercise in the morning was more likely to occur following a period of extended (>5 h) fasting, whereas exercise later in the day occurred sooner following a prior meal (P<0.001). Most participants (52.3%) preferred to exercise during the morning, however, only 30.7% reported having opportunity to exercise at their preferred time. The greatest opportunity to exercise was the early evening (59.0%), and ‘job/work commitments’ (63.9%) was the most frequently reported barrier preventing exercise at preferred times. Conclusions The largest proportion of people perform exercise sessions in the early evening during the week. However, this trend is inverted towards morning exercise during the weekend, which more closely aligns with peoples’ preferences. This indicates that weekday temporal restrictions, possibly resulting from full-time employment, is a primary factor governing exercise timing, with the post-work period clearly identified as the preferential time in which to exercise. As circadian rhythms and feeding status may impact the metabolic response to exercise at different times of the day, future studies should aim to explore the specific effects of evening exercise to maximise ecological validity.