Effects of age and inactivity due to prolonged bed rest on atrophy of trunk muscles

Abstract

This study investigated the effects of age and inactivity due to being chronically bedridden on atrophy of trunk muscles. The subjects comprised 33 young women (young group) and 41 elderly women who resided in nursing homes or chronic care institutions. The elderly subjects were divided into two groups: independent elderly group who were able to perform activities of daily living involving walking independently (n = 28) and dependent elderly group who were chronically bedridden (n = 13). The thickness of the following six trunk muscles was measured by B-mode ultrasound: the rectus abdominis, external oblique, internal oblique, transversus abdominis, thoracic erector spinae (longissimus) and lumbar multifidus muscles. All muscles except for the transversus abdominis and lumbar multifidus muscles were significantly thinner in the independent elderly group compared with those in the young group. The thicknesses of all muscles in the dependent elderly group was significantly smaller than that in the young group, whereas there were no differences between the dependent elderly and independent elderly groups in the muscle thicknesses of the rectus abdominis and internal oblique muscles. In conclusion, our results suggest that: (1) age-related atrophy compared with young women was less in the deep antigravity trunk muscles than the superficial muscles in the independent elderly women; (2) atrophy associated with chronic bed rest was more marked in the antigravity muscles, such as the back and transversus abdominis.

Observation of Age‐Related Decline in the Performance of the Transverse Abdominis Muscle

“…While some authors have used ultrasound imaging to describe the morphology of the core musculature in ageing individuals [16] and changes in morphology during stabilisation [17][18][19] less is known about the effect of ageing per se on the coordinated activation of abdominal muscles.…”

The importance of body mass normalisation for ultrasound measurements of the morphology of oblique abdominis muscles: the effect of age, gender, and sport practice

“…Probably due to different statistical procedures in both mentioned studies, Mannion et al [18] found no correlation between age and OE muscle. In turn, Ikezoe et al (2012) [7] found significantly higher OAM thicknesses in young (mean age 20.0) subjects compared to independent elderly participants (mean age 85.7), but they did not consider body mass as a possible source of the disproportion between examined populations.…”

“…Thus, in a healthy adolescent population there is no correlation between normalised OE and OI thicknesses and participants' age. In other words, in the second decade of life (and probably later, but Ikezoe et al's [7] study needs recalculation), there are no changes independent of body mass in OE and OI thicknesses at different ages.…”

“…Taking into account that in Ikezoe et al's [7] study the young participants were heavier by more than 10 kg compared to the independent elderly group, it may be expected that after body mass normalisation the disproportion in OAM will be less visible or even disappear. In the examined adolescent population, the presence of correlations between age and OAM thicknesses was probably caused by body mass, which physiologically increased between the ages of 10 and 17 years [2].…”

“…The results of this paper suggest that there is a significant positive correlation between the actual value of the OAM and age, whereas for allometric-scaled OI and OE thickness, the correlation with age was low and insignificant. The impact of age on the OAM in the adult population has been examined in prior studies [7,18,22]. Rankin et al [22] found a negative, inconsistent correlation between genders and a very low correlation (r < -0.35) between age and OAM thicknesses in healthy participants aged between 20 and 72; Mannion et al [18] examined a similar population and also found a low, negative correlation between age and OI thickness (standardised beta = -0.264).…”