same way as the physical requirements underpinning mobility: standing up requires strength and power, staying upright requires balance, and walking any distance requires endurance. Any other sequence defies logic. Attempting to ambulate those who cannot lift their body weight out of a chair or maintain standing balance is likely to fail.
Paying attention to the physiological determinants of transfer ability and ambulation and targeting these specifically with the appropriate exercise prescription when reversible deficits are uncovered is most likely to succeed. For example, triceps strength is critical to transfer ability, and improving it has been linked to reduced nursing home admission after hip fracture.74
In some cases, a chronic health condition may benefit equally from resistance or aerobic training (e.g., as in the treatment of depression), but the decision is made based on ability to tolerate one form of exercise over another. Severe osteoarthritis of the knee, recurrent falls, and a low threshold for ischaemia may make resistance training safer than aerobic training as an antidepressant treatment, for example.
Prioritisation requires careful consideration of the risks and benefits of each mode of activity, as well as the current health status and physical fitness level. If one modality of exercise addresses multiple conditions, it is preferable to one that is more limited. For example, in the patient with osteoporosis and depression, resistance training is a more logical choice than aerobic exercise, which can only address the depression.
Patient preference for group versus individual exercise, structured versus lifestyle physical activity, level of supervision desired, and attraction or aversion to specific modalities of exercise must be considered to optimise behavioural change and long‐term adherence.
Resistance training recommendations
Resistance training programmes should be performed 2 to 3 times per week, starting with 1–2 sets and progressing to 2–3 sets of 8–12 repetitions. There has been clear evidence since 1990 that high‐intensity resistance training is feasible and optimally effective for clinical outcomes even in very frail elders. There is no need to wait months to introduce high‐intensity training, which can be achieved by measuring the strength (1 RM) of a muscle group and then using weights equivalent to 50, 60, 70, and then 80% of the 1 RM over the first four days of training. After that, perceived exertion scales can be used to increase the load as tolerated on each subsequent day of training. Perceived exertion can be rated subjectively by the patient and/or objectively by the trainer/caregiver when needed. This method has been used successfully in nursing home residents up to 101 years of age, as well as in older hip fracture patients within 12 weeks of surgery.74 Frailty is not a contraindication to robust exercise; it is, by contrast, one of the most important reasons to prescribe it.
To optimise the functional capacity of frail individuals, resistance training programmes should also include exercises in which daily activities are simulated, such as the sit‐to‐stand exercise. Explosive resistance training (power training) should also be performed if tolerated, especially in the lower limbs, and this type of training can be prescribed at intensities ranging from 20 to 80% of the 1 RM.6,100 However, using a high percentage of loading (80%) results in optimal adaptations of strength, endurance, and power with a single‐exercise paradigm. The concentric (i.e., shortening) phase must be performed as quickly as possible in this type of training. However, special care should be taken with the execution of the exercises to avoid musculoskeletal injuries and screen for rotator cuff and meniscus tears, especially before starting the explosive resistance training in those with osteoarthritis pain. This is the major barrier to power training in older adults but does not preclude traditional slow‐velocity, high‐intensity resistance training.
Balance training recommendations
Many conditions in older adults require balance training before aerobic exercise/gait retraining can be adequately undertaken in ways that are both robust enough to improve clinical outcomes and safe. Although beyond the scope of this chapter, in general, the most effective principles of balance training are as follows:
Narrowing the base of support
Perturbation of ground support
Decrease in proprioceptive sensation
Diminished or misleading visual inputs
Movement of the centre of mass of the body away from the vertical or stationary position
Dual tasking: adding a cognitive distractor or secondary physical task while practising a balance task
Balance training must be challenging to decrease fall risk,199 and therefore the general approach is to practice the most difficult posture or movement without falling in a safe environment (e.g., standing on one leg without hand support) and then move to the next‐harder level, such as closed eyes, as soon as the exercise level is ‘mastered’. This is essentially the same principle that is applied to progressive resistance training: as soon as a load no longer feels ‘hard’ to lift on the perceived exertion scale, it should be increased to ensure continuous, optimum adaptation.
Aerobic and gait training
Gait retraining may include aerobic exercises such as walking with changes in pace and direction, treadmill walking, step‐ups, stair climbing, and other mobility movements. This exercise component may start at 5–10 minutes during the first weeks of training and progress to 15–30 minutes for the long term. The intensity of this exercise component is generally proportional to heart rate and can be increased from moderate to vigorous as fitness and confidence improve. If heart rate is not reliable due to arrhythmias, beta‐blockers or pacemaker, then perceived exertion scales should be used instead.
Multicomponent training
Multicomponent training programmes should include gradual increases in the volume, intensity, and complexity of the exercises, along with the simultaneous performance of resistance, aerobic, and balance exercises. This exercise training modality may also be prescribed in the most vulnerable populations, such as acutely hospitalised older patients179 or institutionalised older adults.4,17,200
In older adults with cognitive impairment, multidomain interventions are under investigation in which exercise training is combined with other treatments such as cognitive training, nutritional alterations, and social enrichment to optimise cognitive performance. However, it is not clear at this time whether such interventions will be more effective than the outcomes seen in robust single‐exercise protocols.2,112,124,201 Supervision is key, and there is no evidence of benefit for low‐intensity, minimally progressive multimodal exercise prescriptions for cognitive outcomes.202 Additional recommendations include consideration of emotional aspects, such as communication challenges, respect, reassurance, and empathy. Simple instructions and use of mirror techniques rather than complicated verbal instructions may help the progression of training and create an empathetic training atmosphere of mindful caregiving for individuals with cognitive impairment.4,17,200 Examples of evidence‐based instructions for mindful caregiving combined with home‐based, progressively intense resistance and balance training for the dementia dyad (caregiver and loved one with dementia) are available (www.strongmindshomecare.org).
VIVIFRIAL Multicomponent Physical Exercise Program to Prevent Frailty and the Risk of Falls is also a good example to follow. Physical exercise guide, Vivifrail (http://vivifrail.com/ resources/), involves mainly lower‐limb muscles (squats rising from a chair, leg press, and bilateral knee extension), upper body (seated bench press), and balance and gait re‐training (e.g., semi‐tandem line walking, single leg standing, stepping practice, walking with small obstacles, proprioceptive exercises on unstable surfaces such as foam pads sequence, weight transfer from 1 leg to the other). Vivifrail has individual prescription passports for older adults depending on the