Not so long ago, lifting weights was limited to athletes and bodybuilders. Developing physical strength was not something that we, the general population, were supposed to be bothered about. Keeping our bodyweight within a certain range and performing plenty of aerobic exercise is what was recommended to maintain optimal health.
More recently however, scientists have identified muscular strength as one of the strongest predictors of mortality available, as well as the dramatic effects of the age-related decline in muscle mass. Inactive adults have been shown to experience a 3-8% loss in muscle mass each decade. This decline is even more profound after the age of 50, when muscle loss occurs at a rate of 5-10% each decade. This is a huge problem for public health because skeletal muscle mass has a very strong influence on many conditions, such as obesity, type 2 diabetes, osteoporosis and heart disease.
I have built a business with a primary objective of making people stronger. As a by-product of this strength training, my clients improve pretty much all markers of good health. They lose body fat, improve insulin sensitivity, improve flexibility, reduce joint pain and improve their ability to function in everyday life.
Looking first at obesity, the largest component (under normal circumstances) of energy expenditure is resting metabolic rate. Resting metabolic rate is elevated in both the short term as a result of a weight training session (more so than traditional aerobic exercise!) and in the long term by an increase in muscle mass (or a reduction in the age-related decline). The likelihood of the food you eat being stored as fat is also massively reduced if you are regularly stimulating your muscle fibres at high intensities. This effect is even more profound if you eat a high protein diet.
Increasing muscle mass and making the tissue more active through weight training is also an extremely effective way to improve insulin sensitivity and prevent type 2 diabetes, an increasingly prevalent condition. Weight training also provides the mechanical forces on bones required for modelling and remodelling, aiding the maintenance of adequate bone strength and density as we age. Interestingly, the largest loads experienced by bones come from muscle contractions (tendons pulling on bone) rather than direct external forces (e.g. landing forces), emphasising the necessity of strength and muscle mass in the prevention of osteoporosis.
In addition to the specific contribution of weight training and muscle mass to the prevention of certain conditions, there is a more general requirement for muscle mass in coping with immediate illness and trauma. When the body is in a stressed state, such as following an injury or fighting an infection or cancer, there is an increase in the liver’s production of proteins required for immune function and wound healing. The building blocks for these proteins (amino acids) are the same as those which make up skeletal muscle. In severe cases, the requirement for these building blocks massively exceeds the rate at which we consume them in our diets; therefore we begin to breakdown muscle tissue to fulfil the requirement. So if there is already a shortage of muscle mass, as there is in most sedentary individuals, the chances of being able to fully recover from serious illness or injury is massively reduced.
The take-home message is that weight training should not be viewed with apprehension by the general public, especially women and the elderly. Instead it should be acknowledged and utilised as the exceptional tool which it is in the fight against disease. In fact, I believe that developing physical strength and lean body mass should be the primary objective of any fitness regimen.
Ruiz, J.R. et al. (2008). Association between muscular strength and mortality in men: prospective cohort study. British Medical Journal, 337, a439.
Wolfe, R.R. (2006). The underappreciated role of muscle in health and disease. American Journal of Clinical Nutrition, 84, 475-482.
Despite a growing understanding of the benefits of resistance training and high intensity interval training, the nation’s go-to fat loss tool still seems to be going out for a jog. Every January we hit the pavements (literally…. again and again and again) with the best intentions. Unfortunately, it turns out jogging is in fact a very flawed fat loss tool.
One reason for this is the idea that the best way to burn fat is to perform long bouts of slow, tedious aerobic exercise. This misconception actually stems from peer-reviewed sports science research. The research shows that we burn the highest proportion of fat for energy at submaximal intensities. What this ignores is the total amount of energy required by the exercise and the amount of energy we burn once the exercise has finished.
A smaller percentage of something big can be greater than a larger percentage of something small! Therefore generally speaking, the harder you train the more fat you will burn. If we also take into account the additional energy we burn after the exercise, referred to as EPOC (excess post-exercise oxygen consumption) in the scientific literature, we can see that we burn more energy after high intensity exercise as well as during it.
The biggest problem I have with jogging is the repetitive impact forces. Biomechanics research shows us that we are subjected to forces greater than double our bodyweight going through one leg with each stride while running. Combine this with the fact that many individuals jogging to lose body fat are both overweight and possess little muscular strength and you have a recipe for joint problems.
It is also extremely difficult to apply the principle of progressive overload to your jogging, which makes it difficult to make continual improvements and adaptations. It is easy to lift one extra kilogram, perform one extra rep or increase the duration of a sprint interval by five seconds. It is more difficult to run 10km 20 seconds faster every week or run an extra 50m with each training run.
Another major problem with long bouts of low intensity exercise is that over the long term it will lead to a loss of muscle mass. This will reduce resting metabolic rate and actually worsen many markers of good health. Resting metabolic rate is generally the greatest contributor to the total number of calories we burn each day, so this has obvious implications to fat loss goals.
Jogging for weight loss also encourages people to tackle weight loss from a calorie approach (count your caloric intake and attempt to burn off more than you consume). This method has many limitations. It does not take into account the macronutrient ratio of the diet and the influence of this on hormone levels and the thermic effect of feeding. A calorie deficit also leads to the loss of lean body mass as well as fat mass. The long term success rate of calorie counting diets is generally estimated to be around 5% in the general population! Combine this with the fact that it is not an enjoyable experience and we can start to see that this may not be the way to go.
All things considered, I believe there is a pretty strong case for us to reconsider jogging being the first point of call for overweight individuals. High intensity interval training and resistance training are more effective options. In cases where these options are not appropriate (due to a lack of facilities, knowledge or the presence of certain orthopaedic issues), I would favour lower impact modes of aerobic exercise like walking or swimming.
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Van Loon, L. et al. (2001). The effects of increasing exercise intensity on muscle fuel utilisation in humans. The Journal of Physiology, 536, 295-304.
Westcott, W. L.. et al. (2009). Prescribing physical activity: applying the ACSM protocols for exercise type, intensity, and duration across 3 training frequencies. Physician and Sportsmedicine, 37 ,51-58.
Shoulder lateral/external rotation exercises are commonly used in rehabilitation from injury and can also be very useful for performance enhancement. The key muscles involved in shoulder lateral rotation are the infraspinatus and teres minor of the rotator cuff and the posterior deltoid.
In rehabilitation from a shoulder injury, lateral rotations are a great way to improve the stability and muscular balance of the joint, improve posture, and when performed with a full range of motion, increase the flexibility. Studies have shown that long term resistance training often leads to posterior shoulder tightness (Barlow et al., 2002), reducing flexibility and leading to injury predisposition. Therefore maintaining a full range of motion can be very beneficial.
Improving the eccentric strength of the lateral rotators is also an effective way of enhancing throwing performance because they have been found to play a big role in decelerating the arm (Jobe et al., 1984). Improving lateral rotation strength can also help you to progress with pressing lifts in the gym due to improved structural balance. If the strength of your infraspinatus and teres minor is poor in proportion to that of your pectorals, you will be pressing with your shoulder in a weak position that will eventually result in injury, often an impingement. It has also been suggested that when an antagonist is too weak, the agonist can actually be inhibited by the brain.
There are a large number of variations on the shoulder lateral rotation exercise and it is important to utilise them for progress. The stimulus is different depending on the equipment you are using (band, cable, dumbbell, etc.) and the tempo, as well as the standard resistance, sets and reps. If returning from injury, it will be necessary to start with high reps, slow speed and low resistance, however when you have a healthy shoulder joint do not be afraid to train in the lower rep ranges too. Possibly the most common lateral rotation exercise, especially following a shoulder injury, is using a thera band. This is an exercise often prescribed by physiotherapists to help balance the muscles of the shoulder and improve the stability of the joint. It is very versatile (you can take a band anywhere), however I would not recommend using this exclusively because it overloads the end range of motion due to the mechanics of using an elastic band. The resistance increases the further it is stretched so you will not be working the muscles evenly throughout the whole range of motion. Using dumbbells and cables in addition to thera bands can rectify this.
There is also benefit to be had from performing rotations with the humerus in different positions. Initially the exercise should be performed with your arm at your side, however you can progress to perform them with your arm abducted to different angles (and horizontally adducted to different angles). When the exercise is done with your arm abducted, the weight of the arm should be supported (rest your elbow on something). This will prevent too much activity from the deltoids and enable you to isolate the correct muscles. Be persistent and consistent with this exercise. It should always be a part of your programme, not just when it is too late and you are rehabbing from an injury.
There are some massive misconceptions about training and eating for the optimal female physique. A lot of women think that hours of cardio and very little food (staying away from all fats) will lead to the body they are aiming for. However this is a long way from the truth. This article will outline and discuss the absolute basics in terms of what you should be doing.
Without meaning to stereotype, when you go in any gym you will invariably see almost every woman on the cardio equipment and only men using the weights and resistance machines. This is due to a couple of myths:
• Myth #1 – If a woman lifts weights she will immediately gain a lot of muscle mass.
• Myth #2 – Long, steady-pace, low intensity cardio is the best way to lose fat.
Firstly, one of the key hormones in muscle building is testosterone. Without it, muscle growth will not occur. Normal testosterone levels in women are around 30-95 ng/dL, whereas in men, normal testosterone levels are around 300-1,200 ng/dL (Webster, 2006). This alone tells us that women will have only a fraction of the muscle growth of men given the same stimulus. In addition, most men who lift weights don’t put on a lot of muscle mass (it takes a hell of a lot more than just lifting weights when you go to the gym to gain considerable muscle mass, even for men!) due to inadequate training protocols, intensity, diet, lifestyle and rest. You therefore do not need to worry about gaining excess bulk. The small amount of muscle mass you will gain will serve to increase your metabolic rate (aiding fat burning) and make your body firmer and curvier in the places you want!
Now regarding cardio: many people have been told and believe that low intensity exercise burns more fat than high intensity exercise. This is a common mistake due to misinterpretation of the facts. The key word is ‘proportion’. At rest, we burn the highest ’proportion’ of fat as an energy substrate. This proportion decreases as we start exercising and as we increase the intensity of exercise due to increased use of other substrates, especially carbohydrate. However the absolute quantity of fat we utilise during exercise increases all the way up to in excess of 55% VO2max (Van Loon et al., 2001), which should be a good-paced jog. In addition, this does not take into account excess post-exercise energy expenditure (EPEE). After training, our metabolic rate will remain elevated for up to several days! This can have even more of an effect on fat loss than the training itself. Studies have found EPEE following resistance training to be significantly greater than following aerobic training even when the intensities were matched by VO2max and duration (Burleson et al., 1998). In addition, in both aerobic training (cardio) and resistance training, studies have found EPEE is higher following higher intensities of training (Haddock & Wilkin, 2006).
There is so much that could be written here, but I will keep it short and simple (this time!). Again I do not mean to stereotype, but many women who take up diets have one thing on their mind: reduce calories. This is true in that if you consume less calories than you burn you will lose weight. However it is not as simple as that if you want to optimise you weight loss and really improve your body and health.
The first, and possible most important thing I will say, is that skipping meals is not the way to go about this. In fact, you will get better results from eating 5-6 small meals every day! Skipping meals and starving yourself will only work briefly before it brings about the starvation response from your body, causing more fat storage and decreased metabolic rate (Wang et al., 2006). This will halt your progress and damage your health. Eating small sensible meals regularly will increase you metabolic rate and make you feel fuller and more energetic (Farshchi et al., 2004), great for beating cravings and exercising.
In terms of what you should be eating exactly, this will again be a very simple overview (keep checking the rest of the site for more). Many people believe consuming fat makes you fat, so go out of their way to avoid any high-fat foods. Not all fats are equal! Natural fats such as omega 3 (as opposed to the trans fats found in processed foods) are good for you and can even promote fat loss (Buckley & Howe, 2009)! The real enemy is high GI carbohydrates. Cut these out and you will see the scales move. One very highly cited study compared a low-fat diet to a low-carbohydrate diet and found the low-carbohydrate diet elicited significantly greater weight loss and adherence (Yancy et al., 2004). Reduce your total carbohydrate intake and ensure that the majority of them come from fruit and veg (not bread and pasta). In addition, a diet high in protein will improve your recovery from exercise (Cockburn et al., 2008), and increase satiety, and metabolic rate (Halton & Hu, 2004).
This should give you a great idea of how to go about achieving your physique goals. Understanding the key concepts is extremely important. The take-home message is that for optimal improvements in body composition, women need to perform resistance training and eat 5-6 small meals per day containing relatively high protein content. In addition, carbohydrate intake should be low (coming from fruit and veg where possible) and limited to low GI sources. Further information will be posted in due course.
The acid-alkaline balance of your body is a very important issue which is commonly overlooked. It is influenced greatly by your diet (Remer & Manz, 1995). A method of estimating the acid loads of particular foods is the potential renal acid load (PRAL). PRAL provides an estimate of the production of endogenous acid that exceeds the level of alkali produced for given quantities of foods ingested daily. This method has been validated in healthy adults; therefore a reliable estimate of acid loads and renal acid excretion can be obtained from diet composition using PRAL (Remer & Manz, 1994). Consumption of a high protein diet will lead to a high acid load. Remer and Manz (1995) found the foods with the highest acid loads were cheese, meat, fish and grain products, while alkaline foods (those with a negative PRAL value) were almost exclusively found in the vegetable and fruit groups.
In sport, alkalisation has been shown to increase the capacity for high-intensity exercise (McNaughton et al., 1999). While in clinical nutrition, infant formulas that contain excessive amounts of acid equivalents have been shown to cause growth retardation and other catabolic effects (Kalhoff et al., 1993). Acid-base status also appears to effect osteology: acidosis-like conditions cause measurable calcium efflux from bone in vitro (Bushinsky & Frick, 2000), and epidemiological studies have found strong positive correlations between the rate of hip fractures in women and dietary animal protein intake (Frassetto et al., 2000).
Essentially, if you are an athlete or you are looking to gain muscle or improve body composition, you will invariably (and correctly) be consuming a diet high in protein. A high protein diet results in increased anabolism (protein synthesis etc.) for muscle building and increased satiety and energy expenditure (due to digestion) for body composition. However it also means consuming a large volume of foods with a high acid load, such as meat and fish. Consequently, this may be impairing your performance and health through acidosis. The solution is to balance out all of the acid loading foods you are consuming with alkaline foods. Precise PRAL values for different foods can be obtained via resources such as the table in this link:
However as a rule of thumb, meat, fish, dairy and grains cause acidosis, while fruit and veg are alkaline. A valuable piece of advice is to consume a portion of fruit or veg every time you ingest protein. When this is difficult, such as when you are out and about having a protein shake, simple solutions are:
-Add lemon or lime juice to your drink.
-Add glutamine to your drink (glutamine very handily has an alkaline effect on the body!).
-Add a greens powder, such as wheatgrass or spirulina.
-An easy way to get your greens in is to make smoothies with spinach (spinach is packed with nutrients and blends up very easily).
-Take easy-to-eat fruit out with you (eg. blueberries).
Just be careful if you are trying to lose weight of what fruits you consume and when. You do not want to be taking on excessive quantities of fructose. These guidelines should have you well on the way to having an appropriate acid-alkaline balance and ever closer to achieving your goals.
Vitamin D is a hormone precursor originally provided by ultraviolet light-induced synthesis of cholecalciferol. However we are now depending more on dietary intake due to lifestyle changes (spending all our time indoors watching TV or on the computer). Adequate vitamin D intake is essential for our musculoskeletal health, however a large proportion of the population is deficient (Holick, 2007) and the problem is worse during the winter months. Here is a list of foods high in vitamin D:
-Cod liver oil
A diet high in oily fish prevents deficiency. You can also take a vitamin D supplement or cod liver oil capsules. Reaching adequate vitamin D levels has a whole range of benefits to your health. It can reduce your risk of chronic diseases such as cancer (Fleet et al., 2012) and type 1 diabetes (Holick, 2004). It has also been shown to protect against osteoporosis (Holick, 2004) and regulate cell growth and healthy cell activity (eg. Parikh et al., 2010). Inflammation has also been reported to be lower in individuals with adequate vitamin D levels (inflammation is the primary risk factor for cardiovascular disease and other conditions) (Wu & Sun, 2011).
This article is not telling you to go and lie in the sun for hours with no protection (that has its own risks associated with it), but to consider your vitamin D intake. If you do not get a lot of sunlight, ensure that you do eat oily fish regularly. Supplementing with vitamin D over the winter months can maintain your levels and help to prevent the depression and low energy levels associated with the dark mornings and evenings.
What to consume immediately prior to sleep is a popular debate among fitness enthusiasts and experts alike. The popular bodybuilding theory was to consume slow-releasing casein protein immediately prior to bed because you will not be eating for eight hours. It was thought that this casein would provide a drip feeding of amino acids into your system overnight. This is a logical idea, and the reason many bodybuilders eat cottage cheese and drink milk before going to bed. However until recently, there was no research to prove that this protein could be digested and absorbed by the body during sleep.
The more recent popular theory goes along the lines of don’t eat anything before bed because food, particularly carbohydrates, suppresses the growth hormone release associated with deep sleep. Again, this makes sense in theory because growth hormone (as the name suggests) stimulates cell growth and is more than likely to play a role in muscle hypertrophy. However, there is also no scientific evidence to prove this. Even linking hormone levels to muscle hypertrophy has proved to be an extremely difficult thing to do. A number of theories exist, such as receptor saturation and a minimum threshold, to suggest that normal physiological fluctuations in anabolic hormones (such as growth hormone) play little to no part in increasing hypertrophy.
A recent study by Res et al. (2012) has shed light on this issue. In the study, participants performed a standardised resistance training session at 8pm after consuming a standardised diet throughout the day. All participants consumed a post workout carb-protein meal, but only half consumed 40g of casein at 11.30pm (the other half had a placebo) before going to sleep at midnight. The results revealed that the casein protein was effectively digested and absorbed by the body during sleep, resulting in a rapid rise in serum amino acid levels, which was maintained throughout the night. Muscle protein synthesis rates were ~22% greater in those who had consumed the casein than those in the placebo group during the 7.5 hr sleep.
This provides strong evidence in favour of casein before bed when muscle growth is the goal. I believe strong data showing greater levels of protein synthesis outweighs the theory about fluctuations in growth hormone. Therefore I recommend a serving of casein shortly before bed. Casein powders are a good option for those eating a low carbohydrate diet and those sensitive to lactose.
Res, P.T., Groen, B. et al. (2012). Protein ingestion before sleep improves postexercise overnight recovery. Medicine & Science in Sports & Exercise, 44, 1560-1569.
A recent study examined the influence of range of motion (ROM) of resistance training on strength and hypertrophy adaptation in elbow flexors. Subjects were assigned to one of two groups: full ROM (group F) and partial ROM (group P). They all trained two days per week for 10 weeks. Both groups significantly increased maximal strength (as measured by 1RM test) and muscle cross sectional area (measured by ultrasound). Strength gains were significantly greater in group F than group P (P ≤ 0.05) and hypertrophy gains were also greater in group F than group P (9.65% increase vs. 7.83% increase) however the difference was not statistically significant.
Oestrogen is the primary female sex hormone and is essential for many physiological functions. However, excessively high levels of oestrogen and its derivatives in both women and men can pose a significant problem to body composition goals and general health. Research has linked excess intracellular levels of oestradiol to:
-Obesity (Key et al., 2003)
-Type 2 diabetes (Livingstone & Collinson, 2002)
-Cardiovascular disease (Murakami et al., 2001)
-Metabolic syndrome (Maggio et al., 2010)
-Prostate cancer (Harkonen & Makella, 2004)
-Breast cancer (Key et al., 2003)
-Gynecomastia (Braunstein, 1999)
Testosterone can be converted to oestradiol by an enzyme called aromatase. In fact, testosterone levels are inversely proportional to oestradiol levels. Therefore the problem of low testosterone levels generally goes hand in hand with excess oestradiol levels, halting fat loss and increasing the risk of the conditions mentioned above.
Oestrogens circulate the body bound mainly to sex hormone binding globulin (SHBG), however only unbound oestrogen can induce biological activity. Therefore changes in the concentration of SHBG will affect the availability of oestrogen at the target cells.
In addition to oestrogen produced by the body, we are exposed to many sources of xenoestrogens in modern life. Xenoestrogens are chemical compounds that imitate oestrogen. Though they differ chemically from oestrogenic substances produced by the body, they have a very similar effect. The most common sources are plastics (especially those containing BPA) and herbicides and pesticides which contaminate our food.
Many diet and lifestyle modifications have been identified to correct the issue of excess oestrogen. I will outline some of the proven ones below.
1. Improve body composition
Adipose tissue (fat) is the greatest peripheral source of aromatase in both men and women. Studies have found oestrogen levels to positively correlate to excess body weight, with levels being up to ten times greater in morbidly obese individuals (Nelson & Bulun, 2001).
2. Drink green tea
EGCG is the main physiologically active polyphenol in green tea and can inhibit the interaction of oestrogen with its receptors (Komori et al., 1993).
3. Stop using plastic bottles and plastic food containers
There are many xenoestrogens used in the manufacturing of plastic products (for example BPA, PBB and Phthalates) so it is a good idea to limit the contact your food and water has with plastic containers as much as is feasibly possible. For example use a stainless steel flask instead of a plastic bottle, and if you use plastic containers ensure they are BPA free. Never use plastic containers in a microwave (use glass and don’t use a microwave!). When plastic is heated it is far easier for xenoestrogens to transfer to your food.
4. Take a probiotic
Taking a good probiotic has been shown to decrease b-glucuronidase activity (Shah, 2007). b-glucuronidase is an enzyme that disrupts our ability to detoxify oestrogen.
5. Eat organic
Although it is more expensive, if possible try to buy organic food to avoid ingesting oestrogenic pesticides and herbicides.
6. Manage blood sugar
High levels of insulin in the blood stream decreases SHBG levels, resulting in more free oestrogen (Kaaks, 1996). This is more evidence in favour of a low-carbohydrate, high protein diet with the majority of carbohydrates coming from food sources that produce a low glycemic response (such as apples, grapefruit and most vegetables).
7. Specific foods
Many foods have been identified to have anti-oestrogenic effects. Cruciferous vegetables (such as broccoli, cabbage and cauliflower) have been found to contain Diindolylmethane (Le et al., 2003), which promotes oestrogen metabolism. White mushrooms have been shown to suppress aromatase activity (Chen et al., 2006), resulting in less conversion of testosterone to oestradiol.
8. Eat flaxseed
Flaxseed is an excellent source of fibre, which in itself has many positive health benefits and can help flush excess oestrogen from the body. It also contains lignans, which stimulate the production of SHBG in the liver, reducing levels of free oestrogen, and inhibit aromatase, decreasing the conversion of testosterone to oestradiol (Adlercreutz et al., 1987). Put it in your smoothies and sprinkle it on your salad.
Many nutrients have been shown to effectively reduce oestrogen by supporting specific pathways of oestrogen metabolism and detoxification. It should be noted however, that adequate levels of these nutrients can generally be achieved through a carefully planned diet.
Magnesium – promotes oestrogen detoxification by promoting methylation and glucuronidation (key pathways) (Muneyvirei-Delale et al., 1998).
Vitamin E – Low levels of vitamin E have been associated with elevated oestrogen levels due to an adverse effect on oestrogen detoxification (London et al., 1987).
Indole-3-carbinol – This compound actively promotes the breakdown of oestrogen to the beneficial metabolite 2-OH (Tiwari et al., 1994).
B vitamins – Act as important cofactors for enzymes involved in oestrogen detoxification (Zhang et al., 2005).
Calcium-D-Glucarate – A natural compound found to aid in the regulation and detoxification of oestrogen by inhibiting b-glucuronidase and increasing the activity of the glucuronidation Phase II pathway (Tully et al., 1994).
Chrysin – This bioflavonoid has been shown to inhibit aromatase (Jeong et al., 1999).
Diindolylmethane – This natural compound promotes healthy oestrogen metabolism by converting it into beneficial metabolites (Mulvey et al., 2007).
10. Stop drinking alcohol
Among its many negative effects on health and body composition, alcohol consumption has been shown to increase oestrogen levels (Fan et al., 2000). If you care about your body, alcohol consumption should be limited to infrequent special occasions.
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