Introduction
Nutrition and physical activity should be addressed in combination with each other. Concentrating on one at the omission of the alternative will return suboptimal outcomes. One of the most significant concepts to recognise is that one’s nutritional evaluation and recommendations should equal the requirements and objectives of the individual and will vary as a result. What I mean by this is that there is no universal nutritional guide or diet that applies to everyone and addresses all of one’s needs. There are three elements that constitute the energy requisite of the individual: namely resting metabolic rate, physical activity, and the thermic effect of food.
Each of these can be influenced by stage of development, genetics, body dimensions, composition, temperature, training circumstances, non-training physical actions, and calorie consumption. For toddlers, youngsters, and adolescents, growth is an additional factor that enlarges the energy requirement.
Resting metabolic rate (RMR) is the principal provider to over-all energy necessity, accounting for roughly 60% to 75% of everyday energy spending. It is a quota of the calories needed for preserving standard body functions such as breathing, heart function, and thermo-regulation (i.e., the energy somebody would use residing in bed for the entire day and doing zilch). Issues that augment RMR include building lean body tissue (i.e. muscle), youth, subsequent development, erratic body temperatures, menstrual phase, and hyperthyroidism. Circumstances that reduce RMR incorporate little-to-no calorie consumption, loss of muscle, and hypothyroidism. Beyond these numerous factors, RMR can fluctuate as far as 20% amongst individuals owing to ordinary genetic disparities in metabolic rate.
The next major constituent of energy necessity is physical activity. Out of all the constituents, this one produces the greatest variability. The quantity of energy necessary for recreational activity hinges on its acuteness, length, and regularity. It is also determined by environmental settings; that is to say, large heat or cold changes enlarge calorie spending. The thermic effect of food is the rise in energy use beyond the RMR which can be calculated for a number of hours after a meal. It is the energy required to digest and assimilate sustenance, which accounts for around 7% to 10% of one’s entire energy demand.
Estimating Energy Requirements
It is problematic, if not unmanageable, to attain an entirely precise appraisal of one’s energy expenditure (in a day). As a result of this, substitute methods are habitually used. One aforementioned technique is to quantity calorie intake. This system is effective if one is sustaining an unchanging body mass, as a steady weight shows that energy consumption usually equates to energy use. For one who is tremendously diligent, the best approach is to evaluate the calorie ingestion from a three-day food record. If that is not preferable, then one can utilise mathematical calculations that coarsely estimate calorie use grounded on the aforementioned factors in the introduction.
Nevertheless, as previously stated, it is essential to note that these are intended as frames of reference, and thanks to the inter- and intra-individual dissimilarity, it is challenging to correctly get hold of the required data.
One system of appraisal can be found in Table 1:
Table 1: Approximated Everyday Caloric Requirements of Males and Females via Activity Level
Activity Level |
Male (kcal/pound) |
Male (kcal/kg) |
Female (kcal/pound) |
Female (kcal/kg) |
Light* |
17 |
38 |
16 |
35 |
Moderate** |
19 |
41 |
17 |
37 |
Heavy*** |
23 |
50 |
20 |
44 |
- *Walking on a flat surface at 4.0-4.8 kilometres per hour, garage labour, electrical professions, woodworking, restaurant jobs, house cleaning, golf, table tennis etc.
- **Walking 5.5 to 6.5 kilometres for every hour, carrying a weight, biking, tennis, dancing etc.
- ***Hiking (with weight) uphill, lumberjack work, substantial labour-intensive excavating, basketball, mountaineering, soccer, rugby etc.
As an example, for a male who weighs 85kg and is highly physically active, the requirement would be (roughly) 4250 kcal (50 x 85).
An alternative for acquiring energy spending is to determine resting energy expenditure (REE), then multiply it by a factor grounded on amount of activity. Quite a few calculations for approximating REE exist. One reliable group of calculations, produced by the World Health Organisation, can be found in Table 2:
Table 2: Estimated Daily Calorie Needs Based on Resting Energy Expenditure (REE) and Activity Level
- To uncover the REE, borrow one of these equations:
Age and Gender |
Calories per day |
Males: 10 – 18 years of age |
(17.686 x weight in kg) + 658.2 |
Males: 19 – 30 years of age |
(15.057 x weight in kg) + 692.2 |
Males: 31 – 60 years of age |
(11.472 x weight in kg) + 873.1 |
Males: Above 60 years of age |
(11.711 x weight in kg) + 587.7 |
Females: 10 – 18 years of age |
(13.384 x weight in kg) + 692.6 |
Females: 19 – 30 years of age |
(14.818 x weight in kg) + 486.6 |
Females: 31 – 60 years of age |
(8.126 x weight in kg) + 845.6 |
Females: Above 60 years of age |
(9.082 x weight in kg) + 658.5 |
- After finding the REE, multiply the REE by one of the following in order to approximate daily calorie requirements:
Level of Activity |
PAL (Physical Activity Level) Rate (x REE) |
Inactive or lightly active way of life |
1.40 – 1.69 |
Active or reasonably active way of life |
1.70 – 1.99 |
Energetic or vigorously active way of life |
2.00 – 2.40* |
- *PAL standards in excess of 2.40 are hard to sustain over an extended period of time
The resulting number embodies the calories that are expected to be used by the individual in a normal day. Those wishing to retain body weight would need to ingest the same number of calories that they spend.
Nutrients
When the dietary intake and energy requirements are identified, the general nutritional necessities can be measured. To appreciate the connection between the body and food, on top of providing nourishment guidance, it is imperative to have a grasp of the six nutrients: protein, carbohydrate, fat, vitamins, minerals, and water.
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Protein
Protein continues to be a key nutrient of concern, especially amongst bodybuilders, weightlifters, and others who participate in resistance training. When endeavouring to address the question ‘How much protein does one need?’ two elements should be deliberated on, energy absorption and the origin of the protein ingested. Protein may be burned for energy when less calories are consumed than are spent. If this is the case, protein ingestion will not be used merely for the anticipated purpose of constructing and supplanting lean muscle tissue. Accordingly, when caloric intake decreases, the protein requirement inevitably rises in unison. This holds true particularly for those dieting. The second feature shaping protein requirements deals with what are termed ‘reference proteins’ (the standard for quality protein), like meat, fish, fowl, dairy goods, and eggs, which are all labelled high-quality proteins. If protein in the diet comes primarily from plant life, then the requirement is most certainly greater.
The literature advocates that the recommended dietary allowance (RDA) of protein for healthy, albeit inactive adults, is 0.8 grams per kilogram of body weight for both men and women.
The WHO classifies the harmless consumption level, a level that is adequate for 97.5% of the populace, at 0.83 grams per kilogram per day.
Although the level agreed here may be appropriate for non-active healthy individuals, it is not suitable for those who have larger needs to help counterbalance protein-amino acid oxidation throughout exercise, mend muscle damage, and form lean tissue. More on this, however, in a later section.
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Carbohydrate
Carbohydrate is essential for the thorough metabolism of fatty acids. Approximately 50-100 grams of carbohydrate (comparable to three to five portions of bread) per day averts ketosis (large quantities of ketones in the blood, where fat is burned for energy but may also lead to organ failure!), which arises from the unfinished breakdown of fatty acids.
Outside that basal necessity, the role of carbs is to deliver fuel for energy (this is the main source of fuel for your brain, heart, and several other organs) and as a result the volume of carbohydrate required depends on one’s entire energy requirement. The requisite fluctuates further depending on the type of exercise. A high-carb diet (equal to 60%-70% of total calories) is ordinarily endorsed for physically active people. Although, it is imperative to note that an assortment of diets, with various carbohydrate, protein, and fat combinations, have been shown to be by the same token, effective. As previously mentioned, a key factor to consider in determining recommendations for carb intake is the training programme. If one is an aerobic endurance competitor, let’s say a distance racer, street cyclist, or triathlete that exercises aerobically for lengthy intervals (90 minutes or more every day), he or she should consume around 7 to 10 g/kg body weight per day. This is comparable to 600 to 750 grams of carbs (2400 to 3000 calories from carbohydrate) per day for someone weighing in at 75kg.
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Dietary Fat
The human body has a small need of nutritional fat. It is projected that individuals ought to ingest no less than 3% of energy from omega-6 fatty acids (beneficial to one’s heart and found in nuts, seeds, oils, and meat) and 0.5% to 1% from omega-3 fatty acids (benefits comparable to omega 6 with sources consisting of fish, oils, and seeds) to avoid deficit. Even supposing the necessity is low, insufficient intake is a likely problem for otherwise hale and hearty individuals that excessively limit dietary fat. Diets with not more than 15% fat may diminish testosterone production, thereby conceivably modifying metabolism and muscle development (for the worse). The suggestion for the general community from the majority of health organisations is that it should bequeath 30% or a smaller amount of the total calories consumed. From this, it is recommended that 20% are derived from monounsaturated or polyunsaturated sources (natural fats), and that not more than 10% come from saturated fats (generally artificial and hydrogenated).
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Vitamins and Minerals
Dietary reference intakes serve as the standard recommendations for the numerous vitamins and minerals the body requires to sustain life-supporting activities. These references take into consideration age, sex, pregnancy, and lactation status. Instead of going into every single vitamin and mineral and the intake requirements here, the reader is referred to the Institute of Medicine’s website: http://www.iom.edu, where DRI tables and links to the full texts of the reports are freely available. Just take note that if one is consuming adequate amounts of food then it is almost certainly true that one is acquiring enough vitamins and minerals.
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Water
Unlike the situation with many other nutrients, it is impossible to set a general requirement for water. Communal knowledge and folklore have placed the need anywhere sandwiched between 1.9 litres to 7.5 litres. Both may well be true, depending on the circumstances. The truth is that water needs adjust based on a multiplicity of factors counting setting, sweating, body surface area, calorie intake, body size, and lean muscle tissue, prompting tremendous disparities. The basic aim of liquid intake is to elude dehydration, that is to say, preserve fluid equilibrium. The state of fluid balance occurs when the water that goes missing from the body through urine, forfeiture from skin and lungs, and through excrement is replaced. The mechanism of thirst is activated at (roughly) 1% dehydration. As a consequence, subscribing to fluid consumption grounded on thirst works rather well to retain fluid balance. Nevertheless, the standard recommendation frequently ranges from 1.4 litres to 2.6 litres a day for the typical person, irrespective of gender.
Goals
Weight Gain
There are two fundamental motives for attempting to gain weight: to refine physical look or boost athletic performance. For weight increase in the form of muscle mass, a grouping of increased food intake and dynamic resistance training is crucial. Muscle matter is circa 70% water, 22% protein, and 8% fatty acids and glycogen (stored form of carbs). If all the additional calories consumed are utilised for muscle development throughout resistance training, hence around 2500 additional kilocalories are necessary for every 0.45 kg (1 pound) growth in lean tissue. This comprises the energy required for tissue assimilation as well as the energy depleted during resistance training. Consequently, 350 to 700 kcal beyond daily necessities would accommodate the calories needed to provide a 0.45 to 0.9 kg (1 to 2 pound) weekly increase in lean tissue on top of the energy requirements of the resistance training programme. To achieve enlarged caloric intake, it is advised that individuals eat bigger portions of foods at mealtime, eat supplementary total calories at every meal, eat regularly, and select higher-calorie sustenance. To accommodate frequent eating, meal replacement beverages (normally protein shakes) can be extremely useful, particularly when a person is not famished. Building muscle mass evidently necessitates larger increases in protein requirements. Protein needs are projected to be 1.2 to 2.0 g/kg body weight per day and could be greater if one’s chief source of protein is plant-based, as is the case with vegetarians and even more so for vegans. This is due to the fact that plant proteins have an inferior biological value with respect to animal proteins. Therefore, the arrangement of a suitable anabolic
incentive (resistance exercise) and absorption of adequate protein allows for a positive nitrogen equilibrium. Positive nitrogen balance arises when protein production surpasses protein degradation. It is also essential to remember that for protein synthesis to transpire in skeletal muscle, all 20 amino acids, in correct quantities, must be present. Lambert and colleagues (2004) have advised a macronutrient proportion for bodybuilders of 55% to 60% carbs, 25% to 30% protein, and 15% to 20% fats. This advice would permit plentiful protein to boost muscle growth, on top of abundant carbohydrate to allow for ideal energy for high-intensity resistance exercise, and still deliver enough fat to maintain acceptable testosterone levels in the bloodstream.
To make things easier, a number of useful guidelines are given below:
Tips to Increase Lean Muscle Mass
- Consume a hyper-caloric diet (one in which more kilocalories than required to sustain current body weight are ingested), about 10% to 15% beyond what is needed to maintain body weight.
- Expand your daily caloric ingestion over five or six meals.
- Participate in a resistance training programme.
- Eat 40% to 50% carbohydrate, 30% protein, and 20% to 30% fat. For supplementary calories, devour high protein, high fat foodstuffs.
- Consume acceptable protein daily (anywhere between 1.5 to 2.0 g/kg per day).
- Routinely ingest whey protein (ideal for building muscle mass), different amino acids (such as the branched-chain amino acids), casein protein (helps prevent muscle degradation), and carbohydrate, predominantly scheduled around your workouts (i.e., pre-, during-, and post- workout mealtimes).
- Consider complementing your diet with creatine (shown to increase strength, muscle mass, and sprint performance; and no other supplement is supported by the same level of positive research).
Conclusively, in order to increase body mass, one must ingest a hyper-energetic diet. Yet, to accentuate lean muscle mass addition, the hyper-caloric diet should be pooled with resistance exercise and a protein intake sufficient to backup protein synthesis.
Weight Loss
One of the ways people can accomplish fat loss is by revising dietary intake, chiefly the quantities and kinds of calories consumed. The straightforward way for one to alter his or her body composition is to modify the energy balance equation. The energy balance equation, when in stability, asserts that energy ingestion (i.e. food consumption) matches energy spending through normal metabolic processes and movement or exercise. When in a condition of energy equilibrium, a person is partaking in a ‘eucaloric’ diet. Due to changeability in body weight, this equation is not constantly in flawless balance. If more food is consumed than calories are spent, a positive energy balance is formed and weight gain is expected to ensue. On the other hand, if fewer calories are consumed than required for normal daily activities and metabolism, an energy shortage is produced.
When athletes must lose weight, one of the first things they habitually do is implement an energy-restricted regimen (hypocaloric diet). These sorts of diets can humbly or brutally decrease total calorie intake. On the risky end of dieting, some individuals embrace diets generally termed very-low calorie diets. The VLCD, as defined by the National Heart, Lung, and Blood Institute is a particular category of diet comprising less than 800 kcal/day. In general, the diet contains comparatively hefty amounts of protein (70 to 100 g/day or 0.8 to 1.5 g protein per kilogram of ‘ideal bodyweight’), somewhat modest carbohydrate (80 g/day), and marginal fat (15 g/day). These diets are regularly consumed in liquid form and are normally encouraged solely for those who are obese, and are working with a dietician or exercise physiologist.
A comparable style of diet, the low-calorie diet (LCD), permits 1000 to 1500 kcal/day of conventional food. A meta-analysis was directed in 2006 on the efficacy of the VLCD and the old-fashioned LCD. The authors established that the preliminary weight loss was larger with the VLCD, but that after a year, the genuine weight loss was virtually the same with both. From a practical perspective, a LCD is far more pragmatic to adhere to on a daily basis. Moreover, owing to the essence of VLCDs, lean muscle tissue is often catabolised to offset the severe drop in protein consumption. Therefore, it is not farfetched to state that LCDs are more suitable for those looking to maintain lean muscle tissue while concurrently improving body composition.
According to Brehm and D’Alessio (2008), studies with durations up to 12 months repetitively reveal that high-protein diets are akin, and possibly superior, to low-protein diets with regards to weight loss, conservation of lean body mass, and improvement in more than a few cardiovascular risk factors. And so, diets that temperately increase protein and modestly limit carbohydrate and fat may well have advantageous effects on body weight and body composition. Even though there are countless studies with contradictory results in the roles of macronutrient ratios in regards to weight loss, it seems that diets moderately higher in protein and somewhat lower in carbs may be the unsurpassed method to successfully maintain muscle mass, while decreasing fat percentage.
With this being said, the following are general principles to consider when starting a weight loss regimen:
- The capacity to achieve and maintain minimal body fat is to some degree genetic.
- Whether one can gain muscle and lose body fat concurrently hinges on his or her training programme and nutrition ingestion.
- An average loss of 0.5 to 1 kg per week denotes a daily calorie shortage of around 500 to 1000 kcal, which can be attained through a mixture of dietary restraint and exercise. Faster degrees of weight loss can bring about dehydration and lessen vitamin and mineral status. Significant amounts of fat loss (at an accelerated rate) will result in loss of noticeable quantities of lean body mass. The rate of 1% total body weight loss per week is a public guideline. So, for example, a 50kg person attempting to lose weight without harm would try for about 0.45 kg weight loss per week, while a 150kg individual would target 1.5 kg per week.
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The diet should be nutritionally balanced and should provide a variety of foods. This is to say, that no single macronutrient should be entirely restricted, as this will have detrimental side effects that may be counterproductive.
Weight loss diet plans are limitless – high protein, low fat, low carbohydrate, this liquid shake, that protein bar, fat thermo-burners, don’t eat at night, eat six times a day, eat one time a day – and the list goes on indefinitely. Undoubtedly, it is impossible to keep up with every new diet that appears on the market. So, in order to best evaluate a diet, one must not do so by the claims it makes, but rather by the foods, and therefore nutrients, that are involved and omitted. Doing so, one can best avoid the many ‘fad’ diets which, severely restrict, potentially cause damage, and demonise the process to improve body composition. Here are some tips to help in spotting these ‘fad’ diets:
- The diet omits one or more groups of foods, which implies that it may be lacking in particular nutrients or that it is too limiting for one to commit to for the long term.
- It overstates one specific food or kind of food. The Cabbage Soup Diet is a great example of this!
- It is very low in calories. Very-low calorie regimens can lead to greater loss of lean muscle tissue, are limited in macro- and micro- nutrients, and may diminish compliance.
- The promoters discourage exercise or point out that it isn’t needed.
- The diet guarantees unrealistically rapid weight loss.
As with the ‘Weight Gain’ section, below are some tips to aid in one’s quest to lose body fat:
Tips to Decrease Body Fat
- Keep a record of all nutritional intake (document the quantity and type of food consumed and moods, times, and locations linked with food intake).
- The easiest approach to decrease body weight is to change your energy balance calculation (i.e., create a negative energy balance).
- It is recommended to diminish total calories consumed by roughly 500kcal per day.
- Lessen caloric intake by dropping the amount of calories resulting from fat in your diet. Maintain or slightly raise protein intake (protein endorsements are 1.5 to 2.0 g/kg of body weight per day) when abiding by a hypo-caloric (restricted) diet.
- Measure body composition often to check that weight loss is coming from stored body fat and not lean muscle mass.
- Make weight loss steady to guarantee maximum fat loss and the safeguarding of lean tissue. For most, a loss of 0.5 kg per week is best.
Summary Points:
- When attempting to lose weight (in the form of body fat), it is imperative for athletes and
- physically active individuals to reduce caloric intake but retain protein intake at 1.5 to 2.0 g/kg of body weight per day.
- When one is endeavouring to gain weight (in the form of lean muscle mass), ingesting in the region of 15% calories beyond maintenance levels is a good starting point.
- Whether the goal is to lose body fat or increase lean muscle mass, it is vital that one follows a well-designed resistance training programme.
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