Experimental Investigation Examining the Effects of Acute Exercise on Implicit Memory Function

Emerging work suggests that acute exercise can enhance explicit memory function. Minimal research, however, has examined whether acute exercise is associated with implicit memory, which was the purpose of this study. Three separate experimental studies were computed (N = 120; Mean age = 21). In Experiment 1, participants were randomly assigned to either a moderate-intensity bout of acute exercise (15-minute) or engaged in a seated control task (15-minute), followed by the completion of a word-fragmentation implicit memory task. Experiment 2 replicated Experiment 1, but instead employed a higher-intensity exercise protocol. For Experiment 3, participants were randomly assigned to either a moderate-intensity bout of acute exercise (15-minute) or engaged in a seated control task (15-minute), followed by the completion of a real world, 3-dimensional implicit memory task. For Experiment 1, the exercise and control groups, respectively, had an implicit memory score of 7.0 (0.5) and 7.5 (0.6) (t(38) = 0.67, p = .51). For Experiment 2, the exercise and control groups, respectively, had an implicit memory score of 6.9 (1.9) and 7.8 (2.4) (t(38) = 1.27, p = .21). These findings suggest that exercise, and the intensity of exercise, does not alter implicit memory from a word fragmentation task. For Experiment 3, the exercise and control groups, respectively, had a discrimination implicit memory index score of 0.48 (0.18) and 0.29 (0.32) (t(38) = 2.16, p = .03). In conclusion, acute exercise does not influence a commonly used laboratory-based assessment of implicit memory but may enhance real world-related implicit memory function.

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The effects of acute exercise on episodic memory function among young university students: moderation considerations by biological sex

Health Promotion Perspectives ◽

10.15171/hpp.2019.14 ◽

2019 ◽

Vol 9 (2) ◽

pp. 99-104 ◽

Cited By ~ 6

Author(s):

Lauren Johnson ◽

Paul D. Loprinzi

Keyword(s):

Episodic Memory ◽

University Students ◽

Verbal Memory ◽

Acute Exercise ◽

Memory Function ◽

Verbal Learning ◽

Memory Task ◽

Moderate Intensity ◽

Term Memory ◽

Main Effect

Background: The objective of this study was to evaluate potential sex-specific differences on episodic memory function and determine whether sex moderates the effects of acute exercise on episodic memory.Methods: A randomized controlled intervention was employed. This experiment was conducted among young University students (mean age = 21 years). Both males (n=20) and females (n=20)completed two counterbalanced laboratory visits, with one visit involving a 15-minute bout of moderate-intensity exercise prior to the memory task. The control visit engaged in a time matched seated task. Memory function (including short-term memory, learning, and long-term memory) was assessed from the RAVLT (Rey Auditory Verbal Learning Test).Results: We observed a significant main effect for time (P<0.001, ƞ2p= 0.77) and a marginally significant main effect for sex (P=0.06, ƞ2p= 0.09), but no time by sex by condition interaction(P=0.91, ƞ2p= 0.01). We also observed some suggestive evidence of a more beneficial effect of acute exercise on memory for females. Conclusion: In conclusion, females outperformed males in verbal memory function. Additional research is needed to further evaluate whether sex moderates the effects of acute exercise on memory function.

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Acute Exercise, Psychological Stress Induction, and Episodic Memory

American Journal of Health Behavior ◽

10.5993/ajhb.43.6.1 ◽

2019 ◽

Vol 43 (6) ◽

pp. 1016-1029

Author(s):

Paul D. Loprinzi ◽

Lauren Koehler ◽

Emily Frith ◽

Pamela Ponce ◽

Dylan Delancey ◽

...

Keyword(s):

Episodic Memory ◽

Psychological Stress ◽

Acute Exercise ◽

Memory Function ◽

Memory Task ◽

Moderate Intensity ◽

Memory Encoding ◽

Moderate Intensity Exercise ◽

Stress Induction ◽

Stressful Environment

Objective: In this study, we evaluated whether exercise prior to memory encoding or during memory consolidation can influence episodic memory function after being exposed to a stressful environment. Methods: We conducted 3 between-group randomized controlled experiments among young adults. We assessed episodic memory (via logic memory task) at the beginning of the experiment and approximately 45 minutes later. Across the 3 experiments, we varied the temporal period (eg, before memory encoding or during consolidation) of the acute bout of exercise (15-minute moderate-intensity exercise) and psychological stress induction. Results: Across all 3 experiments there was a statistically significant main effect for time for memory function, but there were no time x group interaction effects. Conclusion: Memory declined across the 2 assessment periods, but for all 3 experiments, exercise was not associated with memory function after being exposed to a stressful stimulus.

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The Effects of Acute Exercise on Retroactive Memory Interference

American Journal of Health Promotion ◽

10.1177/0890117119866138 ◽

2019 ◽

Vol 34 (1) ◽

pp. 25-31 ◽

Cited By ~ 1

Author(s):

Paul D. Loprinzi ◽

Emily Frith ◽

Lindsay Crawford

Keyword(s):

Acute Exercise ◽

Experimental Studies ◽

Memory Task ◽

Word List ◽

Moderate Intensity ◽

Long Term Memory ◽

Memory Interference ◽

Standard Difference ◽

Size Standard ◽

List Memory

Purpose: Retroactive interference involves the disruption of previously encoded information from newly learned information and thus may impair the consolidation of long-term memory. The objective of this study was to evaluate whether acute exercise can attenuate retroactive memory interference. Design: Three experimental studies were employed. Experiment 1 employed a between-subject randomized control trial (RCT) involving moderate-intensity walking (15 minutes). Experiment 2 employed a between-subject RCT involving high-intensity jogging (15 minutes). Experiment 3 employed a within-subject RCT involving moderate-intensity walking (15 minutes). Setting: University setting. Participants: One hundred twelve young adults. Measures: After exercise, memory interference was evaluated from an episodic word-list memory task, involving the recall of 2 word lists. Results: The pooled effect size (standard difference in means: −0.35; 95% confidence interval: −0.64 to −0.06) across the 3 experiments was statistically significant ( P = .01). Conclusion: We provide suggestive evidence that acute, short-duration exercise may help attenuate a retroactive memory interference effect. Implications of these findings for exercise to improve memory and attenuate memory decay are discussed.

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A Theory of Experimenters: Robustness, Randomization, and Balance

The American Economic Review ◽

10.1257/aer.20171634 ◽

2020 ◽

Vol 110 (4) ◽

pp. 1206-1230 ◽

Cited By ~ 4

Author(s):

Abhijit V. Banerjee ◽

Sylvain Chassang ◽

Sergio Montero ◽

Erik Snowberg

Keyword(s):

Decision Maker ◽

Real World ◽

Robust Performance ◽

Control Groups ◽

Trade Off ◽

Performance Guarantees ◽

Important Concern ◽

Expected Performance ◽

And Control ◽

Shed Light

This paper studies the problem of experiment design by an ambiguity-averse decision-maker who trades off subjective expected performance against robust performance guarantees. This framework accounts for real-world experimenters’ preference for randomization. It also clarifies the circumstances in which randomization is optimal: when the available sample size is large and robustness is an important concern. We apply our model to shed light on the practice of rerandomization, used to improve balance across treatment and control groups. We show that rerandomization creates a trade-off between subjective performance and robust performance guarantees. However, robust performance guarantees diminish very slowly with the number of rerandomizations. This suggests that moderate levels of rerandomization usefully expand the set of acceptable compromises between subjective performance and robustness. Targeting a fixed quantile of balance is safer than targeting an absolute balance objective. (JEL C90, D81)

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Exercise and Retrieval-Induced Forgetting

Psych ◽

10.3390/psych1010030 ◽

2019 ◽

Vol 1 (1) ◽

pp. 405-411

Author(s):

Justin Cantrelle ◽

Paul Loprinzi

Keyword(s):

Acute Exercise ◽

Retrieval Practice ◽

Memory Task ◽

Moderate Intensity ◽

Control Group ◽

Moderate Intensity Exercise ◽

Parallel Group ◽

Main Effect ◽

Induced Forgetting ◽

Experimental Group

Retrieving a subset of items from memory can cause forgetting of other related items in memory, referred to as retrieval-induced forgetting (RIF). This type of forgetting (RIF) is thought to be related to working memory and executive control processes, of which are known to be influenced by acute exercise. The objective of this study was to evaluate whether acute exercise could accentuate RIF. A two-arm, parallel-group randomized controlled intervention was employed. Participants (N = 40) were randomized into one of two groups, including an experimental group (15-min of moderate-intensity exercise) and a control group (time-matched seated task). Retrieval-induced forgetting (RIF) and retrieval practice (RP) were assessed from a category-exemplar memory task. There was no significant main effect for RIF and no group by RIF interaction, suggesting that acute exercise did not alter RIF more than the control group. There was a significant main effect for RP, but there was no group by RP interaction. These RP findings align with the RIF findings, indicating that acute exercise did not alter RP more so than the control group. In conclusion, our experimental results do not provide support for an association of acute exercise on retrieval-induced forgetting or retrieval practice.

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Effects of Acute Exercise and Learning Strategy Implementation on Memory Function

Medicina ◽

10.3390/medicina55090568 ◽

2019 ◽

Vol 55 (9) ◽

pp. 568 ◽

Cited By ~ 2

Author(s):

Paul Loprinzi ◽

Faith Harris ◽

Kyle McRaney ◽

Morgan Chism ◽

Raymond Deming ◽

...

Keyword(s):

Heart Rate ◽

Acute Exercise ◽

Learning Strategy ◽

Memory Function ◽

Strategy Implementation ◽

Moderate Intensity ◽

Exposure Level ◽

Cue Integration ◽

Learning Techniques

Background and Objectives: Long-term potentiation (LTP), the functional connectivity among neurons, is considered a mechanism of episodic memory. Both acute exercise and learning are thought to influence memory via an LTP-related mechanism. Limited research has evaluated the individual and combined effects of acute exercise and learning strategy implementation (e.g., 3-R technique, cue-integration) on memory, which was the purpose of this study. Materials and Methods: For Experiment 1, participants (n = 80; Mage = 20.9 years) were randomized into one of four experimental groups, including Exercise + Learning (E + L), Learning Only (L), Exercise Only (E), and Control Group (C; no exercise and no learning strategy implementation). The exercise stimulus involved an acute 15-min bout of lower-intensity (60% of heart rate max) walking exercise and the learning strategy involved the implementation of the 3-R technique. Experiment 2 (n = 77; Mage = 21.1 years) replicated Experiment 1 but addressed limitations (e.g., exposure level of the memory task) from Experiment 1 and employed a higher-intensity bout of exercise (77% of heart rate max). Experiment 3 (n = 80; Mage = 21.0 years) evaluated these same four experimental conditions but employed a cue-integration learning strategy and a moderate-intensity bout of acute exercise (64% of heart rate max). Results: These three experiments demonstrate that both learning techniques were effective in enhancing memory and we also provided evidence of a main effect for acute exercise (Experiment 3). However, we did not observe consistent evidence of a learning by exercise interaction effect. Conclusions: We demonstrate that both acute exercise and different learning techniques are effective in enhancing long-term memory function.

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The Impact of Acute Exercise Timing on Memory Interference

Perceptual and Motor Skills ◽

10.1177/0031512521993706 ◽

2021 ◽

pp. 003151252199370

Author(s):

Lindsay K. Crawford ◽

Jeremy B. Caplan ◽

Paul D. Loprinzi

Keyword(s):

Associative Memory ◽

Acute Exercise ◽

Memory Task ◽

Cued Recall ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Memory Interference ◽

Exercise Timing ◽

Vigorous Intensity ◽

The Impact

This study evaluated whether the timing of acute exercise can attenuate a memory interference effect. Across two experiments, participants completed an AB/AC memory task. Participants studied eight word pairs; four denoted AB (e.g., Hero – Apple) and four control (DE) pairs. Following this List 1, participants studied eight additional word pairs (List 2); four denoted AC, re-using words from the AB pairs (e.g., Hero – Project) and four control (FG) pairs. Following their study of both lists, participants completed a cued recall assessment. In Experiment 1 (N = 100), an acute exercise bout occurred before the AB/AC memory interference task, and the participants’ three lab visits (successive conditions) were control, moderate-intensity (50% HRR; heart rate reserve) exercise, and vigorous-intensity (80% HRR) exercise. In Experiment 2 (N = 68), the acute exercise occurred between List 1 and List 2, and the participants’ two lab visits (successive conditions) were a (80% HRR) vigorous-intensity exercise visit and a control visit. Across both experiments, we observed evidence of both proactive and retroactive interference ( p < .05), but acute exercise, regardless of intensity, did not attenuate this interference ( p > .05). Acute moderate-intensity exercise was better than control or vigorous-intensity exercise in enhancing associative memory ( p < .05), independent of interference. In Experiment 2, vigorous intensity exercise was associated with more pronounced interference ( p < .05). Our results suggest that acute exercise can enhance associative memory performance, with no attenuation of interference by exercise.

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Experimental Effects of Acute Exercise on Episodic Memory Function: Considerations for the Timing of Exercise

Psychological Reports ◽

10.1177/0033294118786688 ◽

2018 ◽

Vol 122 (5) ◽

pp. 1744-1754 ◽

Cited By ~ 25

Author(s):

James T. Haynes ◽

Emily Frith ◽

Eveleen Sng ◽

Paul D. Loprinzi

Keyword(s):

Episodic Memory ◽

Prospective Memory ◽

Acute Exercise ◽

Memory Function ◽

Moderate Intensity ◽

Long Term Memory ◽

Memory Encoding ◽

Short Term ◽

Term Memory

Our previous work employing a between-subject randomized controlled trial design suggests that exercising prior to memory encoding is more advantageous in enhancing retrospective episodic memory function when compared to exercise occurring during or after memory encoding. The present experiment evaluates this potential temporal effect of acute exercise on memory function while employing a within-subject, counterbalanced design. In a counterbalanced order (via Latin squares), 24 participants completed four visits including (1) exercising (moderate-intensity walking) prior to memory encoding, (2) exercising during memory encoding, (3) exercising after memory encoding, and (4) a control visit (no exercise). Retrospective memory function (short term and long term; 24-hour follow-up) was assessed from a multitrial word list. Prospective memory was assessed from a time-based task. Compared to all other visits, short-term memory was greater in the visit that involved exercising prior to memory encoding (F = 3.76; P = .01; η2 = .79). Similar results occurred for long-term memory, with no significant effects for prospective memory performance. We provide robust evidence demonstrating that acute moderate-intensity exercise prior to memory encoding is optimal in enhancing short-term and long-term memory function when compared to no exercise as well as exercising during and after memory encoding.

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Combined effects of acute exercise and hypoxia on memory

Physiology International ◽

10.1556/2060.2020.00017 ◽

2020 ◽

Vol 107 (2) ◽

pp. 337-348

Author(s):

M. Jung ◽

I. Brizes ◽

S. Wages ◽

P. Ponce ◽

M. Kang ◽

...

Keyword(s):

Acute Exercise ◽

Recall Performance ◽

Acute Hypoxia ◽

Memory Function ◽

Cued Recall ◽

Moderate Intensity ◽

Combined Effects ◽

Hypoxia Exposure ◽

Memory Interference ◽

Recall Memory

AbstractNo previous studies have evaluated the potential combined effects of acute exercise and acute hypoxia exposure on memory function, which was the purpose of this study. Twenty-five participants (Mage = 21.2 years) completed two laboratory visits in a counterbalanced order, involving 1) acute exercise (a 20-min bout of moderate-intensity exercise) and then 30 min of exposure to hypoxia (FIO2 = 0.12), and 2) exposure to hypoxia alone (FIO2 = 0.12) for 30 min. Following this, participants completed a cued-recall and memory interference task (AB/AC paradigm), assessing cued-recall memory (recall 1 and recall 2) and memory interference (proactive and retroactive interference). For cued-recall memory, we observed a significant main effect for condition, with Exercise + Hypoxia condition having significantly greater cued-recall performance than Hypoxia alone. Memory interference did not differ as a function of the experimental condition. This experiment demonstrates that engaging in an acute bout of exercise prior to acute hypoxia exposure had an additive effect in enhancing cued-recall memory performance.

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Experimental Effects of Acute Exercise in Attenuating Memory Interference: Considerations by Biological Sex

Medicina ◽

10.3390/medicina55070331 ◽

2019 ◽

Vol 55 (7) ◽

pp. 331 ◽

Cited By ~ 2

Author(s):

Johnson ◽

Crawford ◽

Zou ◽

Loprinzi

Keyword(s):

Acute Exercise ◽

Memory Task ◽

Moderate Intensity ◽

Adult Males ◽

Moderate Intensity Exercise ◽

Factorial Anova ◽

Biological Sex ◽

Memory Interference ◽

Main Effect ◽

Randomized Controlled Experiment

Background and Objectives: The objective of this experiment was to evaluate the effects of acute exercise on memory interference and determine if this potential relationship is moderated by sex. Materials and Methods: A randomized controlled experiment was conducted (N = 40), involving young adult males (n = 20) and females (n = 20) completing two counterbalanced visits (exercise and no exercise). The exercise visit involved an acute (15 min), moderate-intensity bout of treadmill exercise, while the control visit involved a time-matched seated task. Memory interference, including both proactive interference and retroactive interference, involved the completion of a multi-trial memory task. Results: In a factorial ANOVA with the outcome being List B, there was a main effect for condition (F(1,38) = 5.75, P = 0.02, n2p = 0.13), but there was no main effect for sex (F(1,38) = 1.39, P = 0.24, n2p = 0.04) or sex by condition interaction (F(1,38) = 1.44, P = 0.23, n2p = 0.04). Conclusion: In conclusion, acute moderate-intensity exercise was effective in attenuating a proactive memory interference effect. This effect was not moderated by biological sex.

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