The Exercise Prescription
Maria A. Fiatarone Singh, John Sutton Chair in Exercise, Nutrition, and the Older Woman, 2000
The most important element of the resistance training prescription is the intensity of the load used. This point cannot be overemphasized, as it is the most common reason that strength training programs fail to increase strength in clinically meaningful ways. Intensity refers to the relative force that must be generated by the muscle to overcome or move the resistance through space. In isometric exercise, there is no external movement, but relative degrees of intensity can be attainted by contracting the muscle group against a fixed resistance with various amounts of force. It is evident from many decades of research and clinical practice that muscle strength and size are only increased significantly when the muscle is loaded at a moderate or high intensity. Loads which are equivalent to at least 60% of the maximal capacity (the one repetition maximum, or 1RM) of the muscle are needed for adaptation. In general, the higher the intensity, the more robust the adaptation, with a range from 60 to 90% of the 1RM usually appropriate. Thus, if you test someone’s strength and they can lift ten pounds, then the appropriate stimulus for training (as soon as the technique is mastered) is six to nine pounds for that muscle group.
Prediction of pre-eclampsia
Pankaj Desai in Pre-eclampsia, 2020
This is one more clinical test that became popular and has been quite extensively researched and studied. It was also called the “isometric exercise test”. It was rated positively when the systolic blood pressure increased by ≥15 mmHg during isometric exercise or decreased ≤14 mmHg immediately after isometric exercise for a time period of about 30 minutes. This makes it a time-consuming test. More than two decades of study reported high sensitivity (81.8%) and specificity (68.4%) for predicting pregnancy-induced hypertension (PIH) compared to other risk factors.3 Besides other handicaps, this test like the roll-over test was incompetent for its positive predictive value. This again means that it is good to screen women who will not develop pre-eclampsia, but this is not a good test to predict if women will develop pre-eclampsia. These limitations of the hand-grip test made its use in clinical practice restricted. As a result, this test is now relegated to the confines of history.
Exercise and rehabilitation
Clive Handler, Gerry Coghlan, Marie-Anne Essam in Preventing Cardiovascular Disease in Primary Care, 2018
All muscle groups should be exercised and stretched. Isometric exercise should be performed carefully and after guidance and is not recommended for patients with certain cardiac conditions (see below). The level and duration of exercise should be tailored to the individual. This can be done in primary care but requires input from a trainer or physiotherapist or nurse with advice from the GP about the patient’s cardiac condition and if there are any restrictions on how much the patient should do. Generally, even in patients with heart failure, coronary heart disease, recent uncomplicated myocardial infarction, or heart surgery, a progressive programme of exercise is safe and beneficial. There are very few absolute contraindications to starting an exercise programme. Unstable angina with rest pain, severe breathlessness at rest or critical aortic stenosis, preclude exercise training.
Effect of exercise and physical activity on blood pressure in adults with resistant hypertension: a protocol for a systematic review
Published in Physical Therapy Reviews, 2020
Suranga Dassanayake, Gisela Sole, Gerard Wilkins, Margot Skinner
Among the types of exercises, aerobic exercise is the most highly recommended to reduce blood pressure [23, 24]. A recent meta-analysis explored the effectiveness of aerobic exercise for hypertensive populations, and included 14 studies with 860 participants. Results showed significant mean differences in the experimental and control groups, for SBP of 12.26 mmHg (95% CI: 15.17 to 9.34) and 6.12 mmHg (95% CI: 7.76 to 4.48) [3]. A reduction in blood pressure above 4.4 mmHg is considered as a clinically significant change [28] and a 10 mmHg reduction in SBP will reduce all cause of mortality by 13% [29]. Resistance exercises have also been shown to have a positive effect on lowering blood pressure in HT [30–32] and have been recommended as a supplement to aerobic exercise to reduce blood pressure in HT [33]. A recent meta-analysis which examined dynamic resistance exercise as a stand-alone therapy (64 trials, n = 2344) showed a mean reduction of 5.7 mmHg (95% CI: 9.0 to −2.7) and 5.2 mmHg (95% CI: 8.4 to 1.9) for SBP and DBP respectively [30]. Isometric exercise is the other form of exercise which has been shown to reduce blood pressure, as demonstrated in results published in a range of systematic reviews and meta-analyses [34–36].
Exercise parameters for the chronic type B aortic dissection patient: a literature review and case report
Published in Postgraduate Medicine, 2021
Donald C. DeFabio, Christopher J. DeFabio
The patient’s medication regimen was designed to maintain favorable hemodynamics overtime; therefore, it is imperative the rehabilitative exercises avoid sudden shifts in hemodynamic load. Specifically, isometric exercise ought to be avoided because this can create a significant increase in systolic, diastolic, and mean arterial pressure during activity. Consequentially, this outweighs the post isometric autonomic modulation and produces a reduction of BP with repeated isometric exercise [12]. HIT has been found to be superior to moderate, long duration cardiovascular exercise for improving: cardiorespiratory fitness; endothelial function and its markers; insulin sensitivity; markers of sympathetic activity; and arterial stiffness [13]. With respect to the exercise goals of the patient in this report, HIT is also required as an activity specific training for the patient to return to recreational sport. AT exercise beyond short duration intervals in this demographic has not been studied. However, short duration of 1–4 minutes may provide the cardiorespiratory and biochemical benefits without excessive increase in BP or mean arterial pressure. Regarding resistance exercises, incorporating a longer rest interval between sets and repetitions limits the risk for an insidious increase in BP during the workout session [2].
Acute effects of repetitive peripheral magnetic stimulation following low-intensity isometric exercise on muscle swelling for selective muscle in healthy young men
Published in Electromagnetic Biology and Medicine, 2021
Tetsuya Hirono, Tome Ikezoe, Masashi Taniguchi, Shusuke Nojiri, Hiroki Tanaka, Noriaki Ichihashi
Maximum isometric knee extension torque was measured before exercise. After sufficient warm-up, the participants exerted their maximum voluntary knee extension torque for approximately 3 s with verbal encouragements. The peak torque during a 3-s contraction was defined as maximum strength. The measurements were performed twice with an interval of 60 s, and the largest value was defined as the maximal voluntary contraction (MVC). After more than 2 min of rest, the participants were asked to report their self-perceived fatigue in their knee extensors. After the investigator confirmed they were not fatigued, the participants performed the isometric knee extension exercise at the target torque of 30% of MVC. The low-intensity protocol exercise is widely used in clinical settings and rehabilitation. Exerted torque and the target torque were displayed on a monitor that was located 1 m in front of the participants. They were instructed to exert their knee extension torque over the target torque of 30% of MVC during their voluntary contractions. The low-intensity isometric exercise was performed in three sets; one set comprised 10 repetitions of 5 s contractions and 5 s rest intervals, and inter-set intervals were 60 s. Each exerted torque during the low-intensity exercise was recorded, excluding the initial 1-s torque, which was considered the increasing phase. The recorded torques were normalized to MVC, and the averaged torque (%MVC) was calculated.
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