Older adults tend to lose muscular strength because muscle cells
get larger in size.
attach to the nervous system.
increase in number.
get smaller in size.
The correct answer and explanation is :
The correct answer is: get smaller in size.
Explanation:
As adults age, they generally experience a gradual decline in muscle mass and strength. This condition, known as sarcopenia, is primarily due to a decrease in the size and number of muscle fibers. The process can be attributed to various factors, including hormonal changes, lack of physical activity, and altered nutritional intake, all of which contribute to the reduction in muscle mass.
How muscle cells change with age:
- Muscle fibers get smaller in size:
As people age, the muscle fibers—particularly the type II fibers, which are responsible for fast-twitch, high-intensity contractions—shrink in size. The decline in these fibers leads to a loss of muscle strength and power, making it harder for older adults to perform physically demanding tasks. Smaller muscle fibers are less capable of generating force, which directly impacts functional abilities. - Decreased muscle fiber number:
In addition to the reduction in size, the number of muscle fibers also declines with age. The loss of motor neurons that stimulate muscle fibers leads to the atrophy of some fibers. The remaining fibers may hypertrophy (enlarge), but this compensatory mechanism is not enough to fully offset the total loss in muscle mass and strength. - Alterations in the nervous system:
The nervous system plays a crucial role in muscle strength. As we age, there is a reduction in the efficiency of the nervous system’s ability to activate muscles. The number of motor neurons declines, and the remaining neurons may become less effective at recruiting muscle fibers to produce force, further exacerbating the loss of muscle strength. - Hormonal and lifestyle factors:
Hormones such as testosterone and growth hormone, which play a significant role in maintaining muscle mass, decrease with age. Combined with a sedentary lifestyle, poor nutrition, and other health conditions, these factors contribute to the reduction in both the size and number of muscle fibers.
In conclusion, muscle strength in older adults is primarily compromised by the reduction in muscle fiber size. Proper nutrition, strength training, and physical activity can help mitigate the effects of sarcopenia and maintain muscle health.