Physical fitness improves memory in children

A Finnish study involving 338 older adults (average age 66) has found that greater muscle strength is associated with better cognitive function.

Muscle strength was measured utilising handgrip strength, three lower body exercises such as leg extension, leg flexion and leg press and two upper body exercises such as chest press and seated row.

A number of studies have found that physical exercise can help delay the onset of dementia, however the ability of exercise to slow the decline once dementia has set in is a more equivocal question. A large new study answers this question in the negative.

Various forms of dementia, including Alzheimer's, involve brain network problems. Brain regions are not coordinating as well as they should; white matter is dysfunctional, impairing communications. It has even been suggested that problems in the default mode network (the "resting state" of the brain) may be the ultimate driver of the pathological characteristics of Alzheimer's, such as amyloid plaques, tau tangles, and brain atrophy. Regardless of the order of events, it does seem that network dysfunction is one of the big problems in dementia.

A small pilot study, in which participants had brain scans and working memory tests before and after single sessions of light and moderate intensity exercise and after a 12-week long training program, has shown that immediate cognitive effects from exercise mirror long-term ones. Participants who saw the biggest improvements in cognition and functional brain connectivity after single sessions of moderate-intensity physical activity also showed the biggest long-term gains in cognition and connectivity.

An Australian study involving 102 older adults (60-90) has concluded that physical fitness and arterial stiffness account for a great deal of age-related memory decline.

A rat study comparing different forms of exercise has found that running was much more effective than HIIT or resistence training in generating new brain cells.

Most exercise studies involving rats have used running wheels, and the benefits of these for the creation of new neurons in the hippocampus (adult neurogenesis) have been well-demonstrated. This study used two other (rather ingenuous) strategies to mimic high-intensity interval training and weights training.

A study involving 30 previously physically inactive older adults (aged 61-88) found that a three-month exercise program reversed some brain atrophy.

Participants included 14 with MCI. The exercise program included moderate intensity walking on a treadmill four times a week over a twelve-week period. On average, cardiorespiratory fitness improved by about 8% as a result of the training in both the healthy and MCI participants. Fitness was assessed using peak oxygen capacity rates.

Moderate intensity exercise can benefit memory performance

Three experiments involving a total of 59 people provides more evidence that moderate intensity exercise (e.g., brisk walking, water aerobics, cycling) is enough for cognitive improvement. Indeed, moderate intensity exercise had the most beneficial effect on memory performance.