Strength Training

Original Editor - Manisha Shrestha

Top Contributors - Lucinda hampton, Manisha Shrestha, Cameron Wells, Kim Jackson, Tony Varela, Damon Harrell, Dante Gracia, Rucha Gadgil, Candace Goh and Wanda van Niekerk  

Introduction

Squatting with resistance band for upper extremity

Resistance training (also known as strengthening exercise) increases muscle strength by making muscles work against a weight or force. Resistance exercise is an anaerobic exercise.

• Different forms of resistance training include using free weights, weight machines, resistance bands and your own body weight.
• A beginner needs to train two or three times per week to gain the maximum benefit.
• Client should complete a pre-participation health screening and consult with professionals eg doctor, exercise physiologist, physiotherapist or registered exercise professional, before starting a new fitness program.
• Participant should rest each muscle group for at least 48 hours to maximise gains in strength and size.
• Vary workouts to help client push past a training plateau

Examples Of Resistance Training

Different types of resistance training include:

• Free weights – classic strength training tools such as dumbbells, barbells and kettlebells.
• Medicine balls or sand bags – weighted balls or bags.
• Weight machines – devices that have adjustable seats with handles attached either to weights or hydraulics.
• Resistance bands – these provide resistance when stretched. They are portable and can be adapted to most workouts. The bands provide continuous resistance throughout a movement.
• Suspension equipment – a training tool that uses gravity and the user's body weight to complete various exercises.
• Body weight – can be used for squats, push-ups and chin-ups (convenient, especially when travelling or at work).

Effect of Resistance Training

Strength training stimulates a variety of positive neuromuscular adaptations that enhance both physical and mental health. Physical and mental health benefits that can be achieved through resistance training include:

• Improved muscle strength and tone.
• Maintaining flexibility, mobility and balance, which can help maintain independence in ageing.
• Weight management and increased muscle-to-fat ratio – might be even more beneficial than aerobic exercise for fat loss.
• May help reduce or prevent cognitive decline in older people.
• Greater stamina – as you grow stronger, you won’t get tired as easily.
• Prevention or control of chronic diseases such as diabetes, coronary artery disease, arthritis, back pain, depression and obesity.
• Pain management.
• Improved posture.
• Decreased risk of injury.
• Increased bone density and strength and reduced risk of osteoporosis.
• Improved sense of wellbeing – resistance training may boost self-confidence, improve body image and mood.
• Improved sleep and avoidance of insomnia.
• Increased blood glucose utilization
• Reduced resting blood pressure
• Improved blood lipid profiles
• Increased gastrointestinal transit speed

Criterion Measures

There are various guidelines for prescribing progressive resistance exercise training which is person-centred (ie based upon age and health conditions).

Prior to progressive resistance exercises, it is very important to undergo a pre-participation health screening to ensure exercise training can be safely initiated.

Exercise testing is performed the following reasons:

• diagnostic (i.e identify abnormal physiologic responses)
• prognostic (i.e identify adverse events)
• therapeutic (i.e.gauge impact of a given intervention) purposes
• physical activity counselling
• designing a prescribed exercise programme.

One Repetition Maximum (1RM)

There is an inverse relationship between the amount of weight lifted and the number of repetitions. Strength training literature is often based on a percentage of one-repetition maximum (1RM) in order to define the individualized intensity of training to ensure a participant's safety.

• 1RM is defined as the maximal weight an individual can lift for only one repetition with correct technique.
• The 1RM test is most commonly used by strength and conditioning coaches to assess strength capacities, strength imbalances, and to evaluate the effectiveness of training programmes

It can be either calculated directly using maximal testing or indirectly using submaximal estimation methods.

• There are many different formulas to estimate your 1RM, all with slightly different calculations. The most popular (and proven accurate1) one is the Brzycki formula from Matt Brzycki:

weight / ( 1.0278 – 0.0278 × reps ) 

If you just managed to lift 100 kg for five reps, you’d calculate your 1RM like this:

100 / ( 1.0278 - 0.0278 × 5 ) = 112.5 kg

Evidence

There are various guidelines (majorly, American College of Sports and Medicine and American Heart Association) for the prescription of resistance exercises in a healthy population and population with different co-morbidities and different age groups.

Resistance Exercises and Chronic Diseases

Abdominal obesity, insulin resistance, hypertension, and dyslipidemia are major factors for chronic diseases like cardiovascular disease. Although the mechanisms for improvement may be different, both aerobic endurance exercise and resistance training appear to have similar effects on bone mineral density, glucose tolerance, and insulin sensitivity.

Resistance training assists the body in expending calories via an increase in lean body mass and basal metabolic rate helping in maintaining body composition.

It has been shown to improve function in post-coronary patients (by offering greater development of muscular strength, endurance, and mass) and chronic obstructive pulmonary disease (COPD) patients, as well as to reduce discomfort in people with low back pain and arthritis. In addition, strength training has proved effective for decreasing depression and for reducing the risk of metabolic syndrome, cardiovascular disease, and premature all-cause mortality.

Cardiovascular Disease (CVD)

Blood Pressure Lowering Treatment Trialists Collaboration, 2014 reported that the magnitude of resistance exercise-induced reductions in SBP (5–6 mmHg) and DBP (3–4 mmHg) are associated with an 18% reduction of major cardiovascular events.

A study was done by Mcleod et al, 2019 recommended low-to moderate intensity resistance exercise training(RET) (30–69% of 1RM) is safe and effective even in individuals with CVD or at risk for developing CVD.

According to the AHA, a comprehensive resistance-training program of 8 to 10 exercises for 20 to 30 minutes with an intensity of ≈50±10% of 1 RM with a minimum of 2 days per week and, if time permits, progress to 3 days per week is recommended. Exercise need to be done at a comfortably hard level (13 to 15 on the RPE [rating of perceived exertion]) and without valsalva maneuver. Progession of exercise can be done by increasing 5 % of weight if the participant can comfortably lift the weight for up to 12 to 15 repetitions. If the participant cannot complete the minimum number of repetitions (8 or 10) using good technique, the weight should be reduced.

Type 2 Diabetes

American Diabetes Association, 2014 has reported lifestyle modifications (i.e diet and exercise) were associated with a greater reduction on glycemic control than medication with more emphasis on aerobic exercise training. However there are other studies showing benefits of resistance exercise on glycemic control.

There is a contradictory result showing the level of intensity of resistance exercises in glycemic control. But the study done by Mcleod et al. 2019, recommends the inclusion of general whole-body resistance exercises twice in week in routine without worrying about exercise intensity.

Cancer

There is a role for resistance exercise in reducing cancer risk, cancer recurrence, cancer mortality, and improving prognosis during adjuvant therapies. In breast and prostate cancer, resistance exercise has been apparent. Further work needs to be done to address the optimal dose, intensity, and mechanisms specific to resistance exercise-induced benefits to cancer.

Resistance and the Older Population

With an increase in age, there comes various co-morbidities and fragility syndrome. Among those fragility syndrome, sarcopenia and osteoporosis are most common conditions which decline of physical mobility, increase the risk of fall and increase co-morbidities.

Evidence suggests that resistance exercises can play a vital role in the improvement of functional mobility than aerobic exercises in the older adult. Since resistance exercise is a potent stimulus for muscle hypertrophy and increasing bone density which is affected by sarcopenia and osteoporosis. Resistance exercise incorporated with combined exercise training ( balance exercise, aerobic exercises) has shown to be the best strategy than resistance exercise alone for improvement in functional mobility in older adults.

Resistance exercise training where one’s own body weight is used for resistance and in which activities of daily living are simulated (i.e., body-weight squat) can improve functional mobility in older adults to a similar extent as conventional RET (requiring external load). Even though high-intensity resistance exercise training (≥70% of 1RM) ) is more beneficial in combating mobility decrement than low-to-moderate intensity RET (30–69% of 1RM), low to moderate RET is helpful.

Resistance exercise:1-4 sets of 8–15 repetitions (at 50–85% of 1RM) often performed to fatigue with rest period 1-2 minutes between each set The regular time required to complete the resistance training program is within 30-45 minutes 2-3 times a week is recommended in this article. Exercise prescription given by ACSM is widely used for the older population.

Resources

• (2014) ACSM's guideline for exercise testing and prescription.
• Resistance Exercise in Individuals With and Without Cardiovascular Disease-American Heart Association
• Effects of weight-lifting or resistance exercise on breast cancer-related lymphedema: A systematic review

Related Pages

• Comparison between the DeLorme and Oxford Principles of Strength Training
• Strength Training versus Power Training
• Strength and Conditioning
• Strength training in prepubescents