Free recall and outdoor running: cognitive and physical demand interference

Abstract

Cognitive resource theory is a proposed explanation for people’s limited ability to perform multiple tasks simultaneously. Reallocation of a restricted supply of cognitive resources to two or more tasks may be detrimental to performance on one or both tasks. Many professionals in high-risk fields, such as those engaged in firefighting, military, and search and rescue missions, face simultaneous mental and physical demands, yet little is known about the resources required to move over the natural terrain these operators may encounter. In the present research, we investigated whether interference was found between outdoor running and a word recall task. As hypothesized, a reduction in word recall was observed in the dual task compared to a recall-alone task; however, the distance run was not significantly different between the dual task and the run-alone task. Subjective reports of workload, task focus, and being “spent” (measures calculated from responses on a questionnaire) were greatest in the dual task. These results support the cognitive resource theory and have important theoretical and practical implications. Further research is required to better understand the type and extent of cognitive resources required by such physical tasks and the potential interference with simultaneous mental tasks.

Appendix

Participants’ VO₂max was estimated using the two models below.

The 1-mile jog test (George et al. 1993)

Test procedure

The biographical details collected from the participant, along with their self-ranking on the activity scale below, was plugged into the formula VO₂max¹ = 100.5 + (8.344*gender) − (0.0744*weight) − (1.438*mile time) − (0.1928*heart rate), where gender is coded 1 for male, 0 for female, weight is given in pounds, the mile time is in minutes and fraction of minutes (e.g., 14:30 = 14.5 min), and the heart rate is taken immediately following the 1-mile jog.

The Jackson non-exercise test (Jackson et al. 1990)

Test procedure

The biographical details collected from the participant, along with their self-ranking on the activity scale below, was plugged into the formula VO₂max² = 56.363 + (1.921*PA-R) − (0.381*age) − (0.754*BMI) + (10.987*gender), where gender is coded 1 for male, 0 for female, and BMI is weight (in kg) divided by height (in m) squared.

Participant activity rating (PA-R)

CIRCLE the appropriate number (0–7) which best describes your general activity level for the previous month.

• Category 1. Do not participate regularly in programmed recreational sport or heavy physical activity.

  • 0—Avoid walking or exertion, e.g., always use elevator, drive whenever possible instead of walking.

  • 1—Walk for pleasure, routinely use stairs, occasionally exercise sufficiently to cause heavy breathing or perspiration.

• Category 2. Participated regularly in recreation or work requiring modest physical activity, such as golf, horseback riding, calisthenics, gymnastics, table tennis, bowling, weight lifting, and yard work.

  • 2—10–60 min per week.

  • 3—Over 1 h per week.

• Category 3. Participate regularly in heavy physical exercise such as running or jogging, swimming, cycling, rowing, skipping rope, running in place, or engaging in vigorous aerobic activity-type exercise such as tennis, basketball, or handball.

  • 4—Run less than one mile per week or spend less than 30 min per week in comparable physical activity.

  • 5—Run 1–5 miles per week or spend 30–60 min per week in comparable physical activity.

  • 6—Run 5–10 miles per week or spend 1–3 h per week in comparable physical activity.

  • 7—Run over 10 miles per week or spend over 3 h per week in comparable physical activity.