Table 3 Cognitive outcomes: findings from systematic reviews and meta-analyses (ordered by quality rating)
Authors | Population | Systematic review results | Meta-analysis resultsc |
|---|---|---|---|
High-quality reviews | |||
Martin et al. [31] | Overweight or obese children (3–18 years) | High quality evidence for an effect of PA on composite executive functions and non-verbal memory, but not cognitive flexibility, inhibition (low quality), attention or visuo-spatial abilities Composite executive functions (s = 3): 2/3 no evidence for an effect, 1/3 showing a positive effect Inhibition control (s = 1): no evidence for an effect Attention (s = 3): no evidence for an effect Working memory (s = 1): no evidence for an effect Visuo-spatial abilities (s = 3): no evidence for an effect Cognitive flexibility (s = 2): no evidence for an effect Non-verbal memory (s = 2): some evidence for a small effect General intelligence (s = 1): some evidence for an effect | Composite executive functions:PA: 0.42 (0.05, 0.78), (s = 1); Exergaming: 0.58 (−0.02, 1.18), (s = 1) Inhibition control: not performed Attention: 0.46 (−0.16, 1.08), I2 =41% (s = 2) Working memory: not performed Visuo-spatial abilities: not performed Cognitive flexibility: −0.06 (−0.37, 0.25), I2 =0% (s = 2) Non-verbal memory: not performed General intelligence: not performed |
Low-quality reviews | |||
Singh et al. [25] | Children and adolescents (3–16 years) | 6 high-quality studies: 10/21 (48%) analyses found a significant beneficial intervention effect, leading to inconclusive evidence | NA |
Critically low-quality reviews | |||
Álvarez-Bueno et al. [38]a | Healthy children and adolescents (4–18 years) | Non-executive functions: 7/7 found improvements; of 4 studies that included multiple intervention groups, two suggested that increases in duration and intensity were associated with greater improvements Executive functions: 29/29 found improvements; of 11 studies that included multiple intervention groups, three did not find differences between the groups Meta-cognition: 15/15 found improvements; of 6 studies that included multiple intervention groups, none found differences in improvements | Non-executive functions:d =0.23 (0.09, 0.37), I2 =21.9% (s = 6, k = 17) Executive functions:d =0.20 (0.10, 0.30), I2 =70.0% (s = 22, k = 42) Working memory:d =0.14 (0.00, 0.27), I2 =48% (s = 9, k = 13) Selective attention / inhibition:d =0.26 (0.10, 0.41), I2 =76.0% (s = 17, k = 24) Selective attention:d =0.13 (−0.07, 0.33), I2 =66.8% Inhibition:d =0.38 (0.13, 0.63), I2 =68.7% Cognitive flexibility:d =0.11 (−0.10, 0.32), I2 =68.7% (s = 4, k = 5) Meta-cognition:d =0.23 (0.13, 0.32), I2 =4.7% (s = 10, k = 21) Higher level executive functions:d =0.19 (0.06, 0.31), I2 =12.9% (s = 7, k = 13) |
de Greeff et al. [24] | Primary school children (6–12 years) | Combined academic achievement and cognition: 9/14 reported positive findings on at least 1 outcome measure, 5 reported no significant findings | Overall cognitive functions:g =0.37 (0.20, 0.55), I2 =64.92% (s = 14, k = 18) Executive functions:g =0.24 (0.09, 0.39), I2 = 34% (s = 12, k = 15) Working memory:g =0.36 (0.10, 0.62), I2 =56.79% (s = 6, k = 8) Cognitive flexibility:g =0.18 (0.01, 0.35), I2 =4.79% (s = 4, k = 4) Inhibition:g =0.19 (−0.04, 0.42), I2 =49.7% (s = 6, k = 7) Planning:g =0.12 (−0.08, 0.32), I2< 0.01% (s = 4, k = 4) |
Gunnell et al. [27]b | Healthy children (1–17.99 years) | Inhibitory control:PA vs none (n = 1248, s = 5): 3/5 —, 1/5 — ↑, 1/5 — ↓; PA vs PA (n = 557, s = 6): 3/6 ↑, 1/6 —, 2/6 — ↑; Multiple comparisons (n = 181, s = 1): 1/1 — Working memory:PA vs none (n = 1804, s = 3): 1/3 —, 1/3 ↑, 1/3 —↑; PA vs PA (n = 487, s = 3): 2/3 —, 1/3 ↑; Multiple comparisons (n = 181, s = 1): 1/1 — Cognitive flexibility:PA vs PA (n = 501, s = 2): 1/2 —↑, 1/2 ↑; Multiple comparisons (n = 246, s = 2): 1/2 —, 1/2 — ↑ Unitary constructs:PA vs none (n = 549, s = 2): 1/2 — ↑, 1/2 —; PA vs PA (n = 472, s = 3): 1/3 ↑, 1/3 — ↑, 1/3 — Attention:PA vs none (n = 1809, s = 8): 5/8 —, 1/8 ↑, 1/8 — ↑; PA vs PA (n = 156, s = 5): 1/5 — ↑, 2/5 ↑, 2/5 —; Multiple comparisons (n = 757, s = 1): 1/1 — ↑ Information processing:PA vs none (n = 1659, s = 5): 1/5 ↑, 4/5 —; Multiple comparisons (n = 265, s = 2): 2/2 — ↑; PA vs PA (n = 448, s = 3): 3/3 — Memory:PA vs none (n = 44, s = 1): 1/1 — Motor speed and learning:PA vs PA (n = 508, s = 2): 1/2 ↑, 1/2 — Composite cognition:PA vs none (n = 1794, s = 3): 1/3 —, 2/3 — ↑ | Not performed given heterogeneity of study designs, PA exposures and outcomes |
Verburgh et al. [37] | Children and adolescents (6-17 years), but one study in young adults | Inconsistent results among 5 studies that reported on the effect of chronic PA on executive functions (one in young adults) | Executive functions across age groups: d =0.14 (−0.04, 0.32), Q =5.1 (s = 5) Planning:d = 0.16 (-0.07, 0.39), Q = 0.89 (s=3) |
Jackson et al. [40] | Healthy children (7–12 years) | 8/8 studies showed a positive effect of PA on inhibitory control, but none were statistically significant in isolation; other domains of executive function were measured too infrequently to perform a meta-analysis | Inhibitory control:d =0.2 (0.03, 0.37), I2 =0% |
Li et al. [30] | Healthy adolescents (13–18 years) | 1/2 studies showed a beneficial effect on cognitive function; of five cognitive function parameters, only one showed significance | NA |
Lees and Hopkins [29] | Children and adolescents (< 19 years) | 1/1 studies showed positive effects of PA on cognitive performance; another study was included in the data table, but not part of the results section or evidence synthesis | NA |
Bustamante, Williams, and Davis [39] | Overweight or obese children and/or adolescents | Quasi-experimental (s = 4): each of the four studies showed some benefit on neural, cognitive or academic outcomes; but the PA was confounded with other elements of the intervention and no control groups were present, thus providing little evidence for PA effects RCT (s = 10, but only 5 independent studies): high quality RCT’s (s = 2) have shown benefits for different executive functions | NA |
Suarez-Manzano et al. [36] | Children and adolescents with ADHD (6–18 years) | 7/7 studies showed a positive effect of PA on cognition, no study revealed a negative association; the systematic practice of PA between 5-20 weeks, 30-90mins at moderate-vigorous intensity (40-75%) produces a chronic effect that improves cognition in young people with ADHD | NA |
Mura et al. [33] | Children (3–18 years) | 7/9 studies showed an improvement in global cognitive performance, 1/9 showed no difference and 1/9 worse intelligence; two of these studies found dose-response relationships, with high dose PA performing better than low-dose PA or control; specific cognitive skills improved in almost all studies (6 studies) | NA |
Vazou et al. [35] | Typically developing children and adolescents (4–16 years) | Aerobic only (s = 7): Significant cognitive outcomes: planning (s = 1), creativity (s = 2), working memory and spatial memory span (s = 4), attentional accuracy and spatial inattention (s = 1), cued recall memory (s = 1) and mathematics fluency (s = 1) Motor skills (s = 4): Improvements in working memory (s = 1), spatial processing/math/reading/concentration (s = 1 study), lower error on attentional task (s = 1), mixed effects (s = 1) Cognitively engaging PA (s = 2): Improved planning (s = 1), and spatial memory, but not verbal memory (s = 1) Aerobic and motor skill (s = 1): No difference in inhibition accuracy or reaction time (s = 1) Motor skills and cognitively engaging PA (s = 7): Improved inhibition (s = 1), attention related to arithmetic (s = 1), parent-rated inhibitory behavioral control and reaction time (s = 1), inhibition (s = 1), attention (s = 1), inattention and hyperactivity (s = 1) and attentional accuracy (s = 1) Aerobic and cognitively engaging PA (s = 8): Improvements in math fluency (s = 2), math and spelling (s = 1), fluid intelligence (s = 1), cognitive shifting (s = 1), memory recall (s = 1), verbal working memory and inhibition (s = 1), time-on-task in classroom (s = 1) Aerobic, motor and cognitively engaging PA (s = 1): Improved receptive attention (s = 1) | Overall cognitive function:g =0.46 (0.28, 0.64), I2 =85% (s = 21, k = 28) PA interventions versus comparison treatments: PA vs no treatment: 0.86 (0.18, 1.55), I2 = 93% (s = 5) PA vs academic instruction: 0.57 (0.32, 0.83), I2 =81% (s = 10) PA vs traditional PE: 0.09 (−0.07, 0.24), I2 = 44% (s = 9) PA combinations vs aerobic PA: 0.80 (−0.08, 1.67), I2 =88% (s = 4) Qualitatively different PA interventions vs comparison: see subgroup analysis in Additional file 9 |