Table 4.
Intervention characteristics and outcomes of included animal studies
| Author | Type of exercise training | Duration of exercise intervention | Duration of each training session | Frequency of exercise training | Intensity of exercise training | Outcomes (cognitive tests) | Main cognitive results | Effect size |
|---|---|---|---|---|---|---|---|---|
| Parsa et al. [98] | Swimming | 12 weeks | 40 min | 5 days/week | ? |
Cognitive memory (novel object recognition test and elevated plus maze) Aversive memory and learning (passive avoidance learning test) |
Swimming training alone insignificantly improved exploratory behaviour, locomotor activity, and passive avoidance memory, and non-spatial cognitive memory compared to sedentary diabetic rats | / |
| Shekarchian et al. [99] | Swimming | 4 weeks |
Week 1–2: 3 × 10 min Week 3–4: 6 × 10 min |
5 days/week | ? |
Working memory (Y maze) Recognition memory (novel object recognition) Spatial memory (MWM) |
Exercise improved all memory aspects in exercising T2DM mice compared to non-exercising T2DM mice |
Elevated plus maze test: Percentage of spontaneous alternation: η2 = 0.02 Total arm entries: η2 = 0.01 Novel object recognition test: Familiar recognition ratio: η2 = 0.04 Novel recognition ratio: η2 = 0.08 MWM: Escape latency: η2 = 0.10 Platform quadrant time: η2 = 0.01 Platform crossings: η2 = 0.01 |
| Jesmin et al. [100] | Treadmill running | 4 months | 30 min/day | 5 days/week | Light intensity: OLETF 7.0 m/min, LETO 10.0 m/min; Moderate intensity: OLETF 12.5 m/min, LETO 20 m/min | Spatial learning memory and retention (MWM) | Shortened swim length and escape latency in both light and moderate exercise groups improved memory |
MWM: Escape latency: η2 = 0.11 Swim length: η2 = 0.08 Memory retention: η2 = 0.16 |
| Lang et al. [101] | Treadmill running | 8 weeks | 37 min/day | 5 days/week | Moderate intensity | Spatial learning and memory (MWM) | Compared with T group, the escape latency of E group was significantly reduced on day 4–5, treadmill exercise significantly increased the number of platform crossings in E group |
MWM: Escape latency: d = − 1.39 Platform quadrant time: d = 1.01 Platform crossings: d = 1.32 |
| Shima et al. [102] | Treadmill running | 4 weeks | 30 min/day | 5 days/week | Moderate intensity (OLETF rats, 12.5 m/min; LETO rats, 20 m/min) | Memory (MWM) |
Escape latency and swim path length of exercising OLETF rats were shortened, without alteration of the speed of swimming, at trials on days 2, 3 and 4 The time spent by OLETF rats in the platform area significantly improved after 4 weeks of exercise |
MWM: Escape latency: η2 = 0.11 Swim length: η2 = 0.15 Platform quadrant time: η2 = 0.16 |
| Shima et al. [103] | Running on a forced exercise wheel bed | 4 weeks | 30 min/day | 5 days/week | Light intensity | Memory (MWM) | No effect of exercise on the escape latency, swim distance or speed in ob/ob mice. The times of crossing the target platform during the probe test in C57BL/6 mice were significantly greater than that in sedentary ob/ob mice, but not than that in exercised ob/ob mice |
MWM: Swim length: η2 = 0.02 Swim duration: η2 = 0.05 |
E group diabetes + exercise group, LETO Long Evans Tokushima Otsuka, MWM Morris Water Maze, ob/ob obese-hyperglycemic, OLETF Otsuka Long-Evans Tokushima Fatty, T group diabetes group, T2DM type 2 diabetes