Urinary incontinence (UI), defined as the involuntary flow of urine, is a social and public health problem. Urinary incontinence not only leads to perineal rashes, pressure sores and urinary tract infections, but also embarrassment and negative self-image. In the incontinent group, there is reduced social interaction, poorer self-assessment of health, low emotional and psychological status, impaired sexual relationships, reduced quality of life and depressive symptoms. Physiotherapists have become increasingly involved in the treatment of female urinary incontinence, such as through physiotherapy to increase pelvic floor muscle strength and endurance, as well as to increase bladder sensibility. To further understand the role of physical therapy in the assessment and treatment of female stress incontinence, Dr. Ghaderi et al. from the Department of Physical Therapy, Tabriz University of Medical Sciences, Tabriz, Iran, conducted a review of the previous literature and summarized it in an article published in the journal J Phys Ther Sci 2014. 1 Types of Urinary Incontinence There are three main types of urinary incontinence: stress incontinence, urge incontinence, and mixed incontinence. Stress incontinence is the involuntary flow of urine that occurs during work or exertion and also when coughing and sneezing. During work and exertion, the intra-abdominal pressure increases and the urethral sphincter is unable to maintain a pressure higher than that of the bladder. Urine spillage can also occur during daily activities such as lifting heavy objects, laughing, jumping, sneezing or coughing. Urge incontinence refers to the leakage of urine during or immediately after the urge to urinate. The bladder contracts abnormally when it is full, so the sensation of urination becomes more intense, making it difficult to ignore and eventually leading to leakage. Urge incontinence is perhaps associated with overactive bladder disease, which is characterized by frequency, urgency and nocturia with or without urge incontinence. Mixed incontinence is a sensation of urgency accompanied by involuntary leakage of urine and is also associated with exertion, work, sneezing or coughing. 2 Pelvic floor anatomy and mechanisms of incontinence The mechanisms of incontinence are related to the structure of the pelvic floor. The pelvic floor is made up of transverse muscles arranged in a dome shape, which is usually regarded as a suspensory structure. The fascia and muscles of the pelvic floor support the bladder, uterus and rectum. The deeper muscles of the pelvic floor include the levator ani muscle and the sciaticococcygeus muscle. During bladder storage, activation of the sympathetic nervous system increases the tension and contraction of the internal urethral sphincter thereby preventing leakage. 3 Pathophysiology of stress incontinence The main anatomical hypotheses for the pathogenesis of stress incontinence are as follows: loss of supportive structures, the “hammock hypothesis” and the neural hypothesis. In addition to these three hypotheses associated with incontinence, there are also risk factors associated with the development of incontinence, such as number of births, age, reduction in collagen volume and elasticity, ethnicity, obesity, smoking, chronic coughing, respiratory disorders, pelvic surgery, chronic constipation, and intake of carbonated beverages. There are also nonspecific risk factors such as pelvic organ prolapse, medications, fluid intake, fecal incontinence, and pelvic pain that can contribute to the development of stress incontinence. Notably, pelvic symptoms that accompany stress incontinence include diaphoretic incontinence, pelvic organ prolapse, constipation, sexual dysfunction, chronic pelvic pain, low back pain, and hip pain. 4 Treatment of stress urinary incontinence In female patients with stress urinary incontinence, physical therapy options include pelvic floor physical therapy, lifestyle and behavioral therapy, and medication, as well as patient education, as summarized in Table 1. (1) Pelvic Floor Physical Therapy The most commonly used treatment for stress urinary incontinence is either pelvic floor muscle exercise (PFME) or specific strength training for the levator ani muscle. The most common treatment for stress incontinence is PFME or specific strength training of the levator ani muscle. The rationale for this treatment is that a strong contraction of the levator ani muscle improves urethral closure and increases support for the pelvic organs. Assuming that the contraction of the pelvic floor muscles is strong enough and timely, it can compress the urethra and interrupt leakage. Since the levator ani muscle is composed of a combination of type I and type II muscle fibers, targeted muscle training can affect the type II muscle fibers, thus assisting the urethral sphincter in preventing urinary incontinence. Kegel exercises can be performed under the verbal guidance or palpation of the therapist to promote contraction of the detrusor muscles.The focus of PFME is on strength training and coordination of motor control of the muscles that make up the abdominal wall, thus stabilizing the lumbosacral muscles. In women with stress incontinence, the effectiveness of PFME training depends on the frequency and intensity of training. For example, previous research suggests that in women with mild to moderate stress incontinence, a program of 2 to 4 seconds of muscle contractions each time, with 15 repetitions for 1 set, and 3 sets of training each day for 8 weeks, provides significant relief from incontinence symptoms in patients. The Knack or diagonal support technique also prevents leakage during increased intra-abdominal pressure, and patients are generally instructed to contract the pelvic floor muscles to prevent leakage prior to an increase in pressure (e.g., prior to sneezing). However, the rationale for these interventions (PFME or behavioral therapy applying Knack’s principles) in patients with stress urinary incontinence is currently poorly understood. And since the maximum efficacy of plyometric training usually peaks 5 months after training, the slightly shorter duration of training in the study is also a shortcoming. In a Cochrane search for PFME, treatment was more effective when women were trained for at least 3 months. It is worth noting that in addition to considering the intensity and duration of PFME therapy, the patient’s posture during training also needs to be considered.Borello-France et al. compared the effectiveness of PFME training in two different postures, such as training in an upright position, such as sitting or standing, and the different therapeutic efficacies associated with training in the supine position. The results suggest that position is not an important influence in PFME training. However, the authors of this article believe that studies are needed to further validate the effect of training position on the efficacy of PFME. In clinical practice, physical therapy for the pelvic floor muscles generally follows the following sequence: first, training in a gravity-eliminating position, then in an antigravity position, and finally in an unstable support plane (e.g., application of a Swiss ball) (see Figure 1 for details). It must also be kept in mind that the closer the motor task is to the functional task, the greater the benefit to the patient. Sequence of training (increasing in difficulty from top to bottom) Physical therapy for stress incontinence is summarized as follows: the patient needs to be made aware of the presence of the pelvic floor muscles; pelvic floor function needs to be assessed and trained in a functional position; the patient needs to be taught to perform contractions of the pelvic floor muscles prior to activities that may lead to leakage; and the patient needs to be taught the PFME program and incorporate training of both fast-fiber contractions and slow-fiber contractions; PFME training must involve muscle fatigue, several times a day for 12 to 20 weeks; patients should be followed up with the therapist once a week at the beginning of treatment, after which the resources available to the patient need to be considered; PFME should be used as a maintenance training program. (2) PFME combined with biofeedback therapy Biofeedback or palpation can be used to clarify whether the patient’s muscles are contracting correctly. In women, feedback can be obtained by placing small electrode pads in the perianal area or by applying electrodes built into the vagina. The application of biofeedback allows the patient to immediately feel the output of the muscles during training. Based on previous information in the literature, PFME combined with biofeedback is not as effective as PFME alone. However, PFME combined with biofeedback may be an effective and acceptable treatment option. A practical treatment strategy would be to combine biofeedback therapy with the initiation of PFME training in patients who have difficulty understanding how to contract or are unable to contract the pelvic floor muscles. (3) PFME combined with electrical stimulation Physical therapists can also utilize electrical stimulation therapy to reduce incontinence. The purpose of electrical stimulation is to increase muscle bulk, normalize reflex activity in the lower urinary tract, and improve circulation to the muscles and capillary system. Stimulation of the pubic nerves can improve urethral closure by activating the pelvic floor muscles. A recent meta-analysis noted that the efficacy of electrical stimulation compared to sham stimulation or PFME was comparable to it in terms of improvement in incontinence symptoms. However, electrical stimulation may be preferred in patients who are initially unable to contract their pelvic floor muscles on their own. (4) Preventive role of pelvic floor muscle training There are no studies on pelvic floor muscle training as a preventive treatment for stress incontinence. Theoretically, strengthening the pelvic floor muscles through specific training can prevent the occurrence of stress urinary incontinence and pelvic organ prolapse. If the pelvic floor has some strength, then muscle contraction has the potential to counteract the increase in abdominal pressure during physical activity. Previous studies have focused on the preventive effect of PFME treatment on incontinence at the time of pregnancy or after delivery. The researchers found that in women who did not have incontinence symptoms, they had stronger pelvic floor muscle strength than incontinent women. The other two studies suggested no preventive effect of PFME training during pregnancy or after delivery. However, it is important to note that the reason for the weaker strength of evidence in these two studies is that their training programs consisted of only one session under the supervision of a midwife or physiotherapist, with no supervision or guidance for subsequent sessions. (5) Barriers to successful implementation of physiotherapy In general, female patients with stress incontinence receive physiotherapy once a week for four to eight weeks. In the treatment of urinary incontinence, family therapy combined with physical therapy or an effective treatment program. In addition, factors such as the patient’s education, activity level, number of deliveries, smoking status, type of labor, and pelvic pain may affect the patient’s ability to properly complete PFME. 4 Conclusion Therefore, in women with stress incontinence, an individualized physical therapy program should be developed and include standard physical therapy interventions. As summarized in Table 1, these interventions provide pain relief, PFME with/without biofeedback or electrical stimulation improves pelvic floor muscle strength and coordination, stability training improves abdominal and/or lumbar stabilizing muscle strength, and patient education includes bladder and/or rectal training, fluid management, and dietary programs.