In this medium case and prospective study we showed how different kinds of exercise affect cognitive function of healthy older adults. 89 adults aged 65 to 75 years without dementia took part in the study; 37 men and 52 women. They were assigned voluntary and non-randomly – due to individually interested subjects – into one control group (CG) and into two exercise groups (EG); the CG consisted of 28 participants with an average age of 67.93 years. The EG was divided into two sub-groups doing either aerobic exercises (for example, walking and jogging) or anaerobic exercises (e.g., stretching, toning, coordination, Stroop training during movement training, equilibrium, muscle activity, etc.). The aerobic sub-group (AEG) consisted of 30 participants with an average age of 68.52 years. The anaerobic group (ANEG) consisted of 31 participants with an average age of 68.20 years. Participants of both EG groups trained three times a week for three months. In contrast, subjects in the CG only took part in the pre-test and the posttest. The SPSS-Analysis Covariance (ANCOVA) showed a significant interaction that indicated beneficial contributions of anaerobic training on memory function.
The beneficial effects of aerobic exercise may not be merely limited to physiological advantages such as increasing oxygen consumption, blood circulation, the number of capillaries, and vascular function. Though, bearing in mind that human brain is one of the neediest oxygen consumers in the body. In addition of oxygen roles in the brain development, it has also shown in the pathological processes and the brain dysfunctions. Accordingly, the increasing of oxygen transportation may be an important factor in improving neuronal growth, cell proliferation, cell survival, and creating more stimulation of neurogenesis. Thus, this is surely established that participants in aerobic activity programs receive suitable levels of physical and psychological health. During physical exercise regional cerebral blood flow, in major cerebral arteries and also blood flow in the internal carotid artery enhances, causing an increase in blood flow to a wide regions of the brain. Aerobic exercise increases oxygen saturation angiogenesis and improves vascular function in brain areas crucial for task cognitive performance. These changes are generally associated with aerobic exercise and endurance exercise. This confirms that the transmission of foodstuffs accompanied by the blood during exercise can improve neurogenesis and act as a useful tool for preventing the cognitive decline in adults’ population. Thus, it could be expected that aerobic exercise increases the rate of oxygen consumption in healthy older adults and enhances performance of cognition. Additionally, aerobic exercise can increase level of BDNF, an effective element for supporting the survival of existing neurons in some areas of the brain including hippocampus, medial temporal lobe, amygdala, frontal, prefrontal and parietal cortices. These are vital areas related to learning process, cognitive function, memory performance, and notably the long-term memory. Also, physical exercise can directly enhance synaptic plasticity by changing the synaptic structure and strength, thus, supports neurogenesis. One of the key mechanisms of exercise and physical activity on the brain is induction of growth factors, which plays an important role in structural and functional changes as well as neuroprotective effects in aging. However, our findings support that the participation in regular aerobic activities can help to preserve cognitive activity and decrease the risk of dementia in older adults’ population.
The results of our study confirmed that both aerobic and anaerobic conditions were able to significantly improve older adults’ visual memory in both short and long-term. In verbal memory (VLMT), the outcomes of aerobic and anaerobic conditions for immediate recall (short-term memory or STM), recall after learning in the 5th trial, recall after interference and delayed recall differed a lot. As shown in the text and results, there were no significant differences between all three groups in immediate recall. It appears that perhaps the verbal short-term memory depends less on physical activity and exercise. In fact, both exercises condition did not create significant changes between both exercise groups and control group (CG). We didn’t find a significant increasing impact of exercise conditions on immediate recall for verbal learning memory.
In all events, the influence of both exercise conditions lead to better results compared to the control group, even though, it was non-significant. Unlike the aerobic group, interventions of anaerobic effects indicate a significant difference at recall after learning (5th trial in VLMT), with the CG, interestingly, in this parameter, we can see a significant difference between ANEG and AEG too. This implies that engaging in the low intensity anaerobic condition even without the need of running can create robust beneficial effects in seniors’ cognition, in contrast to regular running and other systematic aerobic program. Also, taking into the results, we can see that the intervening aerobic condition cannot produce a noteworthy difference at recall after interference in the VLMT with the control group. In VLMT after interference list, in trial 7 when no list is read and subjects are asked to recall as many words as possible from the A list, we can see that the intervening anaerobic condition can produce a significant difference at recall after interference in the VLMT with both the aerobic and control group, and this is more when comparing with the aerobic and control group; the aerobic condition has not only positive effects, but also the negative effect of decreasing the outcomes in this phase (Pre-test M = 45.89, Post-test M = 41.81). This is really unexpected in comparison of low intensity exercises of both aerobic and anaerobic and regarding our results. It seems that mild anaerobic intervention can create better improvements in cognitive functions and memory performance of elderly than aerobic. Though the results are promising, findings of our aerobic group suggest that aerobic exercise is not always as effective as its anaerobic counterpart in influencing cognitive abilities and particularly in memory system.
The results of long-term verbal memory at delayed recall in VLMT are significant for both the aerobic and anaerobic groups when contrasted to the CG. Our results of aerobic condition confirm the results of studies about relationship between older adults’ cognition and level of oxygen consumption (Ramel, Wagner, & Elmadfa, 2004), roles of mitochondria (Blalock et al., 2004; Bratic & Trifunovic, 2010; Dringen, Gutterer, & Hirrlinger, 2000; Loerch et al., 2008; Lu et al., 2004; Miquel, Economos, Fleming, & Johnson Jr, 1980; Pak et al., 2003) and the formation of ROS (Fisher-Wellman & Bloomer, 2009; Radak, Chung, & Goto, 2008); exercise may actually make a difference in the aging process using the aerobic condition (Bishop et al., 2010; Rea, Ventura, & Johnson, 2007; Sánchez-Blanco, Fridell, & Helfand, 2006). It appears that the optimal level of aerobic exercise concerning both intensity and duration, as well as the optimal level of ROS generation may be of importance in brain function (Knez, Coombes, & Jenkins, 2006; Radak et al., 2008). If the modification of the oxygen consumption by physical activity induces the neurogenesis in the brain, a novel idea provides preserving the ability of learning processes and memory function because of the involvement of neurogenesis in the process of cognitive function. Thus, this study proposes the future investigations study effects of aerobic exercises on older adults’ cognitive performance with exact measurement of aerobic condition according to the VO2 max levels of physical aerobic program.
In comparison of the time and duration of memory function, it appears that low and light type of the aerobic and anaerobic intervention can create almost similar improvements in memory performance of elderly. Also, findings of the current work suggest the mild to moderate form of anaerobic exercise is more capable than aerobic programs in improving these brain regions effectively. Anaerobic group participants have performed exercises such as new motor learning, Stroop, neuromuscular, cross-brain and body equilibrium exercises; this caused an increase in brain activity and strengthening of the underlying systems that support brain plasticity – including metabolism and vascular function, cell proliferation, cell survival, neurogenesis – which may have caused in turn the increased cognitive function and memory performance compared to the aerobic group which have repeated only the same aerobic activity.
The intervention of anaerobic condition produces a significant difference on other cognitive function aspects, which are examined in the study. We saw a remarkable differences for both EG in the mirror reading tasks, the Trail Making Test (TMT A&B), verbal intelligence (or MWT-B) and in non-verbal intelligence (or LPS-4). Though, it was more robust at significant level for anaerobic groups. Our findings diverge from the data of previous studies, some of which have failed to observe the benefits of anaerobic exercise on cognitive processes. Although, our results need confirmation in further intervention studies, these results suggest that regular non-aerobic could represent an important and potent protective factor for cognitive dysfunction and dementia in the adult people.
All these points to the decline of memory function in late adulthood are not inevitable, that it can be reversed with light intensity of our anaerobic protocol. It seems that for supporting cognitive function in older adults that have difficulty with performing aerobic exercise such as walking and running, the light intensity form of non-aerobic programs may maintain older adults’ cognitive abilities. Hence, even mild intensity form of voluntary exercise is an important factor to improve neuronal growth, create more stimulate neurogenesis, improve mental performance and increase resistance to brain disorder in the adult brain.
Since, a creation of activity in neuromuscular junction is not dependent on intensity of physical exercise. It is hoped that low intensity physical exercise via movement games and training games can improve older adults’ cognitive function. This kind of activity could be a potent protective factor for cognitive dysfunction and dementia in the adult people. In fact, disability in movement of the elderly in aerobic activities such as walking and running should not be lead to more inactivity. Hence, our findings suggested that practicing motor skills can help to develop older adults’ cognitive abilities. Engaging in new motor skill learning leads synaptic changes and creating new proteins in neurons of the brain. When synaptic junction engages in muscle activity, the facilitating and acceleration of electrochemical transfers and neurotransmitters occur. It appears that increasing of synaptic activity can develop capacity of certain circuits of neurons in the brain and can lead to improvement of the cognitive functions in older adults.
We conclude that the participation in aerobic and anaerobic activity programs receive suitable levels of physical and psychological health. Our study suggests that engaging in light intensity form of regular physical exercise activity involves the aerobic, non-aerobic and motor skill learning among other health benefits, may delay or prevent the onset of cognitive impairment and dementia in non-pathological and normative aging. Though, our findings need confirmation in further intervention and brain morphological studies.