There are several anatomical and physiological changes that the older population experience, affecting overall daily activities and exercise routines. First, the aging of organ systems, where cells undergo apoptosis. This event ultimately affects their integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, respiratory, lymphatic, digestive, urinary, and reproductive systems. Due to these changes, seniors can experience loss of range-of-motion, inability to control normal body temperature, loss of balance, decrease in lean tissue, loss of cardiorespiratory functioning, and several other barriers affecting exercise activity. Within the lymphatic system, seniors produce more antibodies that attack body cells. This can lead to diseases like rheumatoid arthritis and multiple sclerosis, impacting overall mobility, balance, fatigue and proprioception. Specifically in females, estrogen levels continue to decrease, which can lead to heart disease and stroke; 30-50% of mortality in postmenopausal women is linked to cardiovascular disease. Not to mention, osteoclast activity drops significantly, causing bone loss, leading to osteoporosis (Williamson, 2019). However, weight bearing aerobic activity can limit or slow down bone loss (Bendedetti et al., 2018). Another factor is the inability to regulate body temperature. Evaporative cooling is less effective, due to the decrease in sweat glands; radiative cooling also becomes less efficient, because the number of capillaries decreases with age. Therefore, exercise intensity should be adjusted, so the senior exerciser does not overheat. Also, providing a cooler environment will help prevent these uncomfortable side effects. Loss of range-of-motion is also decreased with age, as the amount of synovial fluid decreases and collagen fibers shorten. Due to the lack of movement, muscles will begin to atrophy and joints will begin to deform. This can also lead to a lack of strength and balance, causing a higher chance of falls, ankle sprains and various injuries (Williamson, 2019). Therefore, dynamic and static flexibility exercises should be included in the beginning and end of the workout, to aid in accomplishing full range of motion. Additionally, due to the lack of balance, certain movements may need to be adjusted; instead of performing a squat, a sit to stand from a chair may be more appropriate. To add to this, performing hip flexor and quad stretches in the warm up will help complete the full range-of-motion, without pain or discomfort. Finally, cardiorespiratory health also diminishes with age. There is a decrease in sympathetic nerve activity to the heart, which can lead to decreased ejection fraction, lower maximal heart rate and weaker contractions. Therefore, aerobic activities such as walking, water aerobics, and cycling are preferred over higher intensity aerobic activities. This will also help with regulating core body temperature, and preventing falls and other injuries (Williamson, 2019). 

 

As we age, there are several changes that occur in our body that can make daily activities and exercise more difficult. One's biological age is determined by several factors. While habits such as tobacco use, high stress levels, and obesity can negatively affect our biological age, physical activity is the most influential factor in reducing negative changes that coincide with getting older (Williamson, 2019). Bodies naturally go through apoptosis, where the body's cells begin to die. However, they are then replaced with newer cells. As we get older, the loss of cells can outpace the replacement of newer cells, which results in lack of efficiency over time. Analogous to children, a side effect of this is the inability to control core body temperature. The number of capillaries and sweat glands decline over time, and interferes with their ability to evaporate sweat (Williamson, 2019). Larose et al. (2014) performed a study to determine age related differences in heat loss. They analyzed sixty men in five different age groups. In dry humid conditions, the groups of ages 40-85 years of age produced 13-38% more heat than the 20-30 year old group (Larose et al., 2014). Hence, exercise professionals need to monitor the room's temperature and comfort levels of their senior exerciser.

Senior regulatory systems are significantly affected with age. They can experience a loss of neurons, neurotransmitters, blood flow to the central nervous system and several hormonal level decreases. There also appears to be a correlation between the endocrine system and the muscular and skeletal system. Williamson, (2019) states that the pituitary gland reduces its amount of human growth hormone with age. In return, this affects the strength of skeletal muscles. Gupta & Kumar (2022) states that a decline in hormones such as testosterone, estrogen, insulin-like growth factor (IGF-1), and dehydroepiandrosterone can lead to sarcopenia. They continue to demonstrate that a reduction in these hormones is linked to the occurrence of sarcopenia, which proves that sarcopenia is a result of endocrine failure (Gupta & Kumar, 2022). The article highlights how exercise is crucial in preventing the effects of sarcopenia. Exercise can enhance our immune system, cardiovascular system, and increase muscle strength, and endurance. Muscular force generation and overall physical performance are improved by muscle protein synthesis and muscle fiber growth (Gupta & Kumar, 2022; Williamson, 2019). We can also see this correlation with osteoporosis, which is the condition where old bone breaks down at a faster rate than new bone being developed. In women, bone mass decreases with age, largely due to the loss of estrogen (Williamson, 2019). Also, the skeletal system goes through various changes hindering a seniors mobility, flexibility, coordination and overall range of motion. As humans get older, articular cartilage begins to wear away, collagen fibers shorten and synovial joint fluid is reduced. These side effects can lead to sprains, bursitis, and arthritis (Williamson, 2019). An article from Backer et al., 2020 discusses basal arthritis, which is arthritis of the thumb. This type of arthritis originates at the base of the thumb where the metacarpal bone meets the trapezium bone in the wrist. Basal arthritis causes extreme discomfort and pain, making it hard for sufferers to do everyday activities, such as buttoning a shirt, opening a jar, or gripping a pen to write (Bäcker et al., 2020).

 

The older population is a combination of those over 65 years, along with 50-64 year olds who are experiencing physical limitations, affecting their physical activity. Exercise has a great positive impact on older individuals, and helps delay or prevent certain age-related symptoms. For exercise testing in older adults, a pre exercise evaluation is always recommended. Because older adults will show increased cardiovascular, metabolic or orthopedic problems, testing should be slightly adjusted for them. The initial workload should begin with light intensity of less than three METs. Using a cycle ergometer is the preferred and safer choice, especially due to the prevalence of balance and proprioceptive issues in older adults. It’s also essential to consider the medications being taken and the appropriate heart-rate-max formula to use; the FOX formula (220-age) is unreliable, since most older individuals exceed this. Finally, unless there are signs or a presence of cardiovascular disease, exercise testing can begin with light intensity, unless told differently by a medical professional. Some examples are the 6-minute walk test and the Senior Fitness Test, combining a variety of movements.  Once the assessments are given and evaluated, lighter intensity for both aerobic and resistance training should be applied. This fact is especially true in those who are currently inactive. For individuals with sarcopenia, the EP should apply muscular strength exercises first before aerobic activity, because they are not physiologically capable yet (Liguori et al., 2021). Mayer et al. (2011) cites a study from Burke et al. who did an 8-week program for postmenopausal women with osteoporosis. They gave them several balancing and resistance training exercises. By the end of 8-weeks, the study showed an improvement in isometric muscle force of the knee and ankle joint, as well as increased balance (Mayer et al., 2011).