Sleep regulation is the result of an intricate neural network that coordinates signals from diffuse brain areas to set off sleep, preserve it, and orb between different stages of sleep, ensuring sleep-wake cycles that are restorative over the long haul as well as serviceable in day-to-day living. This regulation relies heavily on the hypothalamus, where many vital nuclei are located, such as the SCN, a primary clock in the brain’s circadian rhythm, and the ventrolateral preoptic area, whose task is to produce sleep by inhibiting neurons promoting wakefulness [24]. The SCN receives direct actine input from the retina via the retinohypothalamic tract, while controlling melatonin secretion in the pineal gland, the rhythm is synchronized with natural light-dark cycles. Ultimately, adjusting endogenous circadian rhythms to external light and darkness. The orexin (hypocretin) neurons in the lateral hypothalamus are key players in maintaining wakefulness: these cells stimulate arousal centers even as they prevent unwanted falls into sleep, so when orexin signaling is lost, people become narcoleptic (Figure 1). Reciprocal interactions between brainstem structures, such as the sublaterodorsal nucleus, which promotes REM sleep by glutamatergic projections, and ventrolateral periaqueductal gray that inhibits it, are necessary for normal sleep architecture: this delicate balance must be protected to ensure a healthy lifestyle [25].

Pain, spasticity, and drug use are crucial factors that have a profound effect on sleep quality, particularly in patients with neurological diseases. The interaction between them often results in fragmented, non-restorative sleep and may even lead to severely compromised health outcomes [26]. In addition, both their discomfort and immobility can bring on secondary musculoskeletal pain, thereby significantly amplifying the adverse effects of sleep [27]. Pharmacological treatment of pain and spasticity can present a paradox where sleep quality is concerned. Opiates and some antispastic drugs like baclofen induce sleepiness or change sleep architecture, reducing the amount of REM and deep sleep, essential for cognitive and emotional function. They also tend to aggravate sleep-disordered breathing, such as central sleep apnea and obstructive sleep apnea. By depressing the function of the respiratory center, opiates may lead to hypopnoea (an abnormal reduction in respiratory rate) [28]. Table 1 provides an overview of how pain, spasticity, and medications influence sleep quality in various neurological conditions, based on previous studies [29–47].

Those with sleep disturbances have their mental, emotional, and physical functions affected in many ways; people suffering from neurological disorders may find that these damages compound their existing deficiencies while also making it more difficult to recover. In terms of cognition, sleep is very important for such processes as memory consolidation, attention, executive function, and learning [48]. At an emotional level, sleep disorders lead to the formation and aggravation of various mood disorders: depression, anxiety, irritability, etc. Lack of sleep alters our emotional regulation; it disorganizes the action of neurotransmitter systems like serotonin and dopamine, which play vital roles in emotional control and dealing with stress, while at the same time disturbing the delicate balance maintained so steadfastly by the hypothalamo-pituitary-adrenal axis [49].

Persistent failure in functional recovery is often accompanied by decreased participation in rehabilitation activities. In addition, there are consequences for rehabilitation failure. For example, insomnia, moodiness, and fatigue arising from sleep disruption are likely to make therapy sessions unbearable or otherwise less than profitable endeavors [50]. This is especially critical for diseases such as PD and MS, where the efficacy of therapeutic interventions depends on factors that are frequently compromised. When these factors are impaired, interventions may yield little to no benefit, and progress can be severely limited despite ongoing efforts. New approaches to treating sleep disorders—such as CBT-I, CPAP for OSA, and customized drug therapy—have been shown to improve sleep quality. This then results in quicker functional gains and increased participation in rehabilitation programs [51].

Quality of life and caregiver burden are not challenges faced solely by patients; they also significantly impact the broader support systems that care for them [52]. When sleep quality is poor, the symptoms of fatigue or pain, the existence of mood disorders, and cognitive impairment all affect the daily life and social behavior of patients. Taken together, these factors decrease perceived quality of life to a big extent. The stress on carers reflects the patient-related sleep problems mentioned previously. Caregivers often never get a good night’s sleep because the patient might move involuntarily at night or be awakened by nightmares or respiratory disturbances that occur with various types of neurological diseases [53].

Aerobic and resistance training are cornerstone interventions in physical therapy and exercise science, each offering unique and complementary benefits for physical health, mental well-being, and sleep quality. Characterized by controlled, rhythmic activities that elevate heart rate and oxygen consumption, such as walking, jogging, cycling, or swimming, aerobic training greatly affects cardiovascular fitness. Further benefits of regular aerobic exercise are its general enhancement of mood regulation and metabolic health, due to the intensified heat-work recovery cycles that promote hormone production and neurotransmitter function in the brain—mood also may be improved because it conforms to usual patterns rather than erratic ones [76]. Establishing a consistent daily routine helps stabilize hormonal levels throughout the day and evening, regardless of ambient light conditions. Through an investigation into pathophysiology, it is discovered that exercise increases circulating catecholamines, which can stimulate vigilance during waking hours but also promote wakefulness and increase the ability to fall asleep. Regular exercise promotes sleep through a general relief of anxiety and depression, improved autonomic balance with increased parasympathetic tone, and restructuring the cycle of circadian rhythms. Furthermore, aerobic exercise decreases systemic inflammation and oxidant attack on cell membranes; both factors are known to disturb sleep—especially in disorders such as OSA, fibromyalgia, or insomnia. With their conventional continuous moderate-intensity training, the symptoms of insomnia were effectively reduced [77]. In recent years, high-intensity interval training (HIIT) has emerged as a popular way to keep fit. First, anecdotal reports questioned whether late-evening HIIT built in breaks might exert a negative influence on sleep. However, new evidence suggests that even at this relative intensity of training, these exercise routines probably do not harm sleep—at any rate, not in healthy people who do not have insomnia [78,79]. Still, future research needs to examine the impact of high-intensity exercise at a late hour on patients suffering from insomnia. Exercise may work on insomnia in several ways. Regular aerobic exercise is associated with increased overall wellness, including cardiovascular health, metabolic efficiency, and weight control [80]. In addition, movement of the body causes physical fatigue, and thus helps one sleep. Regular aerobic exercise has been shown to alleviate symptoms of anxiety and depression, classically seen in intertwinement with chronic insomnia. Exercise also affects the secretion of sleep-influencing hormones, for instance, heightening melatonin and dampening stress activation, which leads to insulin resistance [81].

For populations affected by musculoskeletal, neurological, or long-term illnesses, stretching, positioning, and postural treatment are vital strategies aimed at improving physical function, reducing pain, and improving sleep quality. Stretching exercises are designed to enhance flexibility, ease muscles, and increase the ability of movement, all important for someone with spasticity, arthritis, or chronic pain [82]. When a muscle is held in a lengthened position for a specific duration, static stretching has been found to relieve stiffness and relax muscles. It is especially effective before bedtime because it prepares the body to sleep well. Dynamic stretching entailing controlled movements resembling functional activities is frequently employed during daytime rehabilitation sessions to improve neuromuscular control and prevent injuries. The benefits of stretching also extend to improving the circulatory system, parasympathetic activation to lower stress levels, and eliminating the discomfort resulting from extended periods of immobility or poor posture [83]. Regular exercise has been demonstrated to ameliorate the symptoms of sleep apnea. According to a meta-analysis conducted by Iftikhar et al. [84], those patients with OSA can expect a 32% reduction in their apnea–hypopnea index (AHI) if they engage in exercise training programs regularly for 3–6 months. In a recent study of patients with OSA by Lins-Filho et al [85], HIIT for 12 weeks effectively reduced OSA symptoms (AHI was decreased by 8.6 events per hour), increased total sleep time by 51 minutes and sleep efficiency by 12%, and elevated cardiorespiratory fitness increases to 4.8 mL/kg/min. The HIIT regime was carried out on a treadmill and comprised 5 repetitions each at maximum heart rate (HR_max) for 4 minutes with breaks in between stages for approximately 3 minutes at 50%–55% of HR_max. These results suggest a promising role of intense exercise as a time-efficient and effective method for treating OSA.

Task-oriented and neuromuscular rehabilitation are pivotal in restoring functional impairments and can aid in motor recovery, especially for those with neurological conditions such as stroke, cerebral palsy, PD, or spinal cord injury [82–85]. The combination of task-oriented and neuromuscular approaches has shown significant promise in improving motor outcomes by addressing both the functional and physiological aspects of rehabilitation [86]. Thinking of recovery as a process of relearning functional movements that were once automatic, task-oriented training incorporating neuromuscular facilitation techniques can lead to optimal results for patients with hemiparesis. This combined approach is particularly effective in gait training, as task-specific activities such as walking on uneven surfaces or climbing stairs are coupled with neuromuscular interventions to improve balance, coordination, and the strength of lower limbs [61]. In addition, virtual reality and robotics have become valuable tools in task-oriented, neuromuscular rehabilitation. They provide immersive yet adaptive environments that allow for repetitive practice with feedback delivered in real time [84]. In one study, 40 male patients with sleep disorders were randomly assigned to experimental and control groups. The experimental group received 8 weeks of yoga treatment (yoga sessions in the morning, 90 minutes each session) from September 1994 to January 1995. There were marked improvements in stress scores and self-confidence scores. As regards acute exercise, research indicates that 20–40 minutes of aerobic exercise can sustainably improve anxiety states and mood for several hours [87,88]. The neurobiological mechanism hypothesis posits that active engagement in sports can enhance cognitive function and mental health by inducing structural and functional changes in the brain. Increasing energy outlay through activities might influence sleep patterns, subsequently improving mental health outcomes [89]. In more specific detail, exercise increases metabolism and body temperature, thus promoting sleep to restore the body. A major signal for sleep initiation is the evening decline in body temperature, predominantly brought about by an increase in peripheral skin blood flow.

Rehabilitation must include sleep hygiene tips as part of its overall plan, since sleep quality affects physical, mental, and emotional recovery. Sleep hygiene includes those behavioral things and environmental changes that make sleep better, such as keeping regular working hours, managing one’s environment to promote good rest, and eliminating conditions conducive to tossing and turning at night. In a treatment setting, the population most in need of attention to sleep hygiene comprises those with neurological ailments, chronic pain, or psychological problems. Unfortunately, these are also people generally least likely to get good sleep. Another cornerstone for sleep hygiene training is to change the conditions in which one sleeps. Adding sleep hygiene tips to therapy not only improves sleep but also improves overall recovery rates. Poor-quality sleep reduces neuroplasticity and energy amounts, while exacerbating pain or making it more resistant to treatment. This cascade of problems hinders both therapeutic progress and the restoration of normal function [90]. Conversely, improved sleep quality quickens physical and cognitive rehabilitation through boosting the ability of the nerve cells to regrow, providing emotional comfort, and maintaining a stable supply of energy. Education of practical demonstrations can be used for people who need sleep hygiene practices, and therapy sessions can also help to build up those helpful habits, which will facilitate better sleep (Figure 2).

Occupational therapists and caregivers work together to help people take care of their own daily lives [91]. Occupational therapists focus on enabling individuals to engage in everyday activities that are meaningful and therapeutic, and must address whatever barriers interfere with occupational performance. For example, sleep disturbances are often overlooked in people with physical or mental impairments. Sleep education, environmental alterations, and behavioral strategies are some of the techniques occupational therapists employ to help their clients develop habitual bedtimes, keep a regular schedule of sleep, and arrange living environments that are conducive to sleep. Such a patient-centered model means that treatment is individualized, understood in terms of the culture and circumstances of each person, and integrated with the overall rehabilitation plan for maximum compliance and effectiveness. Combining occupational therapy with cognitive-behavioral strategies simultaneously brings about immediate changes in sleep disturbances while also addressing their extended effect on cognition, emotions, and motor recovery. Poor sleep impairs concentration, memory retention, executive function, and mood—all of which are critical for active participation in rehabilitation or activities of daily living. Through these interventions to improve sleep quality, patients show better cognitive processing, less fatigue, and improved self-regulation of emotional responses. This makes for greater client dependency and progress in therapy. Increasing evidence verifies the efficacy of combined occupational therapy and cognitive-behavioral interventions for improvements in sleep across a wide array of populations. For instance, studies on stroke patients show that when occupational therapists deliver sleep education supplemented with CBT-I instruction, outcomes can be improved markedly in the areas of sleep quality, general mood, and functional performance. Similarly, people with chronic pain or neurological disease processes that target both behavioral and environmental factors report less insomnia severity and better quality of life after combinatorial tactics. Meanwhile, technology-assisted approaches—like telehealth CBT-I applications alongside wearable sleep monitors for data—open new directions in scaling up the spread of such therapies. They also provide quantitative feedback so treatment can be fine-tuned to suit each individual [92].

The comprehensive management of sleep-related illness in rehabilitation settings must involve participation by sleep treatment specialists and rely heavily on CPAP therapy. Patients with neurological problems, such as stroke, TBI, PD, and MS, are particularly prone to sleep disturbances. The former can include OSA, a very common problem in these populations that has pronounced implications for rehabilitation outcome, ranging from cognitive function to motor recovery and overall quality of life [93]. CPAP is still the treatment of choice for moderate-to-severe OSA, which involves repetitive upper airway obstructions at night, with characteristic episodes of hypoxia leading to arousals and reduction in total REM sleep, then followed by fatigue across the course of daytime activities. While untreated OSA in neurological rehabilitation settings not only deprives the brain of needed oxygen during sleep through repeated episodes of apnea followed by arousals, it also slows down cognitive improvement, reduces motor rehabilitation, and makes life more dangerous (e.g., increased cardiovascular risk). Development of CPAP at an early stage is able to greatly improve sleep quality and eliminate daytime drowsiness (Figure 3). It can also enhance neuroplasticity processes, which are crucial for recovery of function, and reduce the possibility of further brain damage. However, rehabilitation populations often face compounded challenges, including reduced cognitive function, limited physical capacity, and minimal motivation or awareness of the potential benefits of therapeutic interventions [94].