Did not receive funding to support this project.

Although more than half of Canadian smokers in 2015 attempted to quit, with one-third attempting more than once, successful smoking cessation (quitting) remains a challenge. Relapse (return to smoking) has been attributed to failures in inhibitory control. Inhibitory control is the ability to suppress actions. Previous studies have identified that aerobic exercise improves inhibitory control and reduces the urge to smoke. This study will examine whether an acute bout of moderate intensity aerobic exercise (i.e. brisk walk on a treadmill) will improve inhibitory control, increase time to first cigarette smoked, and reduce urges to smoke during a brief period of abstinence. Inhibitory control will be assessed using the antisaccade task, which requires the participant to shift their gaze away from a visual target presented to them. Phase I will include assessments of smoking behaviours, physical activity levels, urges to smoke, and inhibitory control. Phase II will consist of a 12-hour smoking abstinence period conducted at home, followed by reassessment of urges to smoke and inhibitory control. Participants will then be randomized to either 20 minutes of aerobic exercise or sitting. Following the intervention, reassessment of urges to smoke, inhibitory control, and time to first cigarette smoked will be conducted.

The participant will be provided a letter of information and an informed consent form. Once they have signed the informed consent form, the following procedures will take place:

Phase I:

• Initial biological confirmation of carbon monoxide reading: Participant will briefly blow air into a Smokelyzer (device which assesses how much carbon monoxide in parts per million is present in the breath of a smoker)

• Baseline questionnaires: Participant will be asked to fill out to the best of their ability the following questionnaires:

  1. Demographic questionnaire (Asks you identifiable information concerning, your age, email telephone number)
  2. Smoking history questionnaire ("What is the approximate date and time of the last cigarette you have smoked?")
  3. Fagerstrom Test for Nicotine Dependence ("How many cigarettes do you smoke each day?")
  4. Godin Leisure-Time Exercise Questionnaire ("In the last 7 days, how many times have you completed mild intensity exercise for 15 minutes or more?")
  5. Physical Activity Readiness Questionnaire ("Do you feel pain in your chest at rest?")
  6. Urge to Smoke ("I have an urge for a cigarette")
  7. Heart rate will be measured with a heart rate monitor. Blood pressure will be measured with an electronic blood pressure cuff.

• Cognitive computer task: Participant will be asked to complete a computer task which assesses inhibitory control (the cognitive ability to suppress responses to stimuli). The Antisaccade Task will be used to assess inhibitory control in this study.

Phase II:

• Smoking abstinence period: The participant will be instructed at the end of Phase I that they will have to complete a 12 hour smoking abstinence period (refraining from smoking cigarettes or consumption of any tobacco products) at home before coming back into the lab. The participant will be also notified that the co-investigator will be able to assess whether they completed this abstinence period through assessing the carbon monoxide reading on the Smokelyzer.

• Biological confirmation of carbon monoxide reading: Participant will briefly blow air into a Smokelyzer (device which assess how much carbon monoxide in parts per million is present in the breath of a smoker). The participant will have to blow below 10 parts per million carbon monoxide to have successfully abstained and thus participate in Phase II.

• Questionnaire: Participant will be asked to fill out to the best of their ability the following questionnaire:

  f. Urge to Smoke ("I have an urge for a cigarette")

• Cognitive Computer Task: Participant will complete the same Antisaccade Task as outlined in Phase I.

• Intervention Participant will be randomly assigned (through a randomly generated number sequence) to either 20 minutes of aerobic exercise or 20 minutes of sitting.

• Aerobic Exercise Intervention: The participant will complete a 20 minute walking exercise on a treadmill.

• Non Exercise: The participant will be in a seated position in the lab waiting room. They will be provided with magazines and computer access.

• Post Intervention:

• Questionnaire: Participant will be asked to fill out to the best of their ability the following questionnaire:

  f. Urge to Smoke ("I have an urge for a cigarette")

The participant will then be told to notify the co-investigator of when they light their next cigarette through a time-stamped email or text message. The time in minutes from when they leave the lab (time: 0) until the message is received will be calculated.

Inclusion Criteria:

• 18-64 years of age
• Smoke at least 10 cigarettes per day (or more) for at least 6 months
• Able to perform a twenty-minute exercise task at a moderate intensity (2/3 of participant's maximum heart rate) without health implications
• Can read and write in English
• Have email or phone number for contacting purposes

Exclusion Criteria:

• Do not have Chronic Obstructive Pulmonary Disease
• Do not have a medical condition that prevents you from exercise (e.g. heart attack in the past year, heart disease, irregular heartbeat, etc.)
• Do not have history of eye injury or neurological impairment
• Do not have an orthopaedic limitation
• Are not pregnant