Exercise Nutrition: Nutritional Recommendations to Maximise Results

We know the importance of following a good nutritional program and the benefits of doing so.

We may also know that combining this with regular physical activity is going to bring the best results for those interested in a complete health and fitness regime.

As trainers and coaches we need to help show people how to do this while achieving as many of the benefits from it. 

The purpose of this article is not to teach you about good exercise nutrition and training, or how to do it (that’s probably a separate article entirely), but to understand the physiological and psychological responses of it, and how that should affect a person’s nutritional approach. 

The Benefits of Exercise and Training

There are a number of health and fitness benefits associated with regular exercise nutrition and training.

We have two main forms of exercise, aerobic and anaerobic.

There are a number of similar benefits to both, but each also provides additional benefits not seen from the other. These have been summarized below:

AEROBIC EXERCISE

Walking, jogging, running, cycling and swimming are all forms of aerobic exercise.

Aerobic fitness can be defined as the ability to take in, transport and utilize oxygen in the body to produce energy. 

With long duration, sub maximal exercise such as walking and running the body uses a combination of fats and carbohydrates to produce energy.

ANAEROBIC EXERCISE

The term ‘anaerobic’ means ‘in the absence of oxygen’ or ‘without oxygen’. During anaerobic exercise, your body’s demand for oxygen is greater than the available oxygen supply. 

While aerobic exercise is fueled by oxygen, anaerobic exercise is fueled by energy stored in muscles. 

Most anaerobic exercise is extremely high intensity, short duration exercise lasting from just a few seconds to minutes. 

This is the direct opposite to aerobic exercise, which involves sustained activity of moderate intensity. 

Exercise Fundamentals

Having an understanding of the exercise fundamentals that apply to both aerobic and anaerobic training ensures that the desired benefits previously mentioned are produced.

Also, it helps us further understand how these types of exercise affect the body and the nutritional demands to best support it. 

ELEMENTS OF TRAINING

There are a number of elements that should be considered when someone undertakes exercise. These key elements are common to both aerobic and anaerobic training but are essentially represented differently due to the differences in training styles. 

It is these key elements that will produce the key benefits of the chosen exercise and force the body to make adaptations. From a nutritional stand point, the person’s nutrition programming should reflect how they have set these training elements. 

Training Volume

The volume of training is essentially the total amount of work completed. For aerobic training the volume is 
typically calculated by the total distance completed i.e. how far they ran, or via total time total time.

Anaerobic training is typically calculated by recording the total number of repetitions per session or the total weight lifted (reps x weight). 

This volume can then be used as a base for each training session, number of training sessions completed in a specific time or the training frequency. 

Training Intensity

Intensity is described as how much ‘effort’ was applied to the session.

For anaerobic work such as weight training, intensity is typically measured as the percentage of the maximal weight that it is possible to lift for 1 repetition in that chosen exercise. 

If someone has a 1 rep max of 100 pounds in the bench press, yet was only lifting 60 pounds, they are working with a training intensity of 60%. 

In relation to this, intensity can also be matched to how close to failure the person goes. So if the person pushes to absolute failure (meaning they can’t complete another rep), then intensity is considered much higher then if they stop short of failure by 2-3 reps. 

For aerobic training, this intensity element is typically classified as a percentage of maximal heart rate. Maximal heart rate can be calculated using the following equation, 

Max heart rate = 208 – (0.7 x age in years)*
*Estimation only.

Therefore someone performing aerobic exercise at 140bpm with a max heart rate of 200 is considered to have an intensity of 70%. 

What we need to understand is that the volume conducted and the intensity used are directly correlated. A change to one element will and should result in a change to the other. Furthermore, these two elements are strongly linked to the type of exercise that should be conducted to achieve this correlation, be it aerobic or anaerobic training. 

The table below shows how these should be correlated:

As you can see, as volume is reduced the intensity can be increased, usually resulting in a transition between aerobic style training to anaerobic. 

Responses To Exercise

So far we have looked at the two different types of training, their benefits and how their fundamental principles should define them. 

Although this alone can help us define the right nutritional settings, we will first look at the physiological and psychological responses of the body to these styles of training. This will improve our knowledge and confidence in the nutritional recommendation we make. 

MUSCULAR RESPONSE

For exercise, it’s clear to say that skeletal muscle is one of the key factors designed to produce the required force to make it happen. 

We should therefore understand its key factors and the response or adaptations we can go through as a result of exercise. 

Aerobic Training Response

Long-term endurance exercise has shown to increase someone’s maximal oxygen uptake, which will result in the ability to deliver more oxygenated blood to the working skeletal muscles. It can also enhance a muscle fibres ability to extract and use oxygen for energy production. 

These responses occur through adaptations that increase the oxidative capacity of muscle, and increase the number and size of mitochondria. 

A further adaptation can result in a transition of type IIx fibres to type IIa fibres in response to aerobic training. 

Anaerobic Training Response

Long-term anaerobic training such as weight lifting will most probably result in increases in muscular strength and size. The primary way that muscle hypertrophy occurs is by growth of individual muscle fibres. Longer term increases in muscle strength result primarily from muscle hypertrophy. 

Increased muscle size, and the force it can produce, has been shown to be directly related to its cross sectional area. Furthermore, a greater rate of growth is typically seen from our type II (fast twitch) fibres than our type I (slow twitch) fibres. Finally, transition of type IIx fibres to IIa frequently occur with this type of training. 

Delayed-Onset Muscle Soreness (DOMS)

DOMS are a common problem for aerobic and anaerobic trainers alike, and are the result of muscle fibre damage. This results in a muscular pain or discomfort approximately 16-24 hours after a training session. This soreness is usually located in the most worked muscles from that training session and can peak around 24-48 hours after.

It is typically associated with exercise that consists of a lot of eccentric loading or movements and causes an inflammatory response within the muscle. This damage is readily repaired with adequate rest and recovery. 

ENDOCRINE RESPONSE

Most people conduct exercise to elicit a response from the body, be it improved fat burning, muscle gain, strength or endurance. 

What we forget is that the neuroendocrine system is also of primary importance to our exercise performance and the adaptations occurred from it. 

Our neuroendocrine system is linked to a whole host of metabolic and hormonal regulations and responses. With exercise, the body responds by releasing a large number of anabolic and catabolic hormones that are triggered to deal with the remodeling and repair of tissue. 

We not only see instant hormonal response patterns to exercise but subsequent adaptations as a result. 

Out of the many hormones, the ones that appear to show the greatest response to exercise (weight training in particular) are:

Testosterone

Weight training has been shown to increase total testosterone levels in men only, which is considered to have one of the strongest links to triggering further anabolic processes and hormones in the body. 

Growth Hormone (GH)

GH, also known as somatotropin, is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans.

Resistance training has been shown to elevate concentrations of GH 30 minutes after exercise, and is similar in men and women. There appears to be no long term changes in resting GH concentrations. 

Cortisol

Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the fasiculata of the adrenal cortex. It is released in response to the stress effects of exercise and similar elevations appear in men and women.

It acts as a catabolic hormone in the body, resulting in a greater release of lipids and amino acids into the blood stream. This can result in protein degradation and decreases in protein synthesis. 

Insulin Like Growth Factors (IGF's)

IGF’s are small polypeptide hormones that are secreted by the liver in response to GH stimulated DNA synthesis. They respond in the body just like ‘insulin’, creating an anabolic environment and boost protein synthesis following resistance training. 

Insulin

Insulin is a peptide hormone, produced by beta cells in the pancreas, and is central to regulating carbohydrate and fat metabolism in the body. It causes cells in the skeletal muscles and fat tissue to absorb glucose from the blood. It is an anabolic hormone with a potent up-regulating effect on muscle protein synthesis.

Serum insulin concentrations have been shown to decrease during an exercise session. 

Catecholamines

Catecholamines are derived from the amino acid tyrosine and the most abundant are adrenaline, noradrenaline and dopamine. These are released from the adrenal glands.

They are important for increasing energy availability, force production and muscle contraction rate.

They are considered part of the ‘fight or flight’ response and elevation of these are seen after (and occasionally before) intense training sessions. 

OVERTRAINING

Overtraining may have become an overused word, and some do not believe it can occur, as the body is a highly adaptable machine. 

What does seem clear is that when we see intense and long lasting elevated responses to exercise, both on a physiological and psychological aspect, overtraining does appear possible. 

The result is usually a short-term decrease in performance capacity, for which restoration may take several days to a few weeks. 

Markers of overtraining: 

Nutrition For Exercise Training

The previous section looked at the benefits of exercise, how it works and how the body responds to it.

As nutrition coaches, it’s important to understand how nutritional/supplemental strategies can indeed have an effect on all of this, and how we adjust our recommendations for someone who is exercising.

We can now look at some of the most researched and effective strategies that we can use to ensure our clients are enhancing the benefits of exercising, and reducing the negatives.

No matter what level of exercise or sport undertaken, the goal should be to always establish a solid nutrition foundation to adequately set the stage for reaching optimal training performance and recovery.

Below are a number of nutritional considerations for people undertaking regular athletic and ​exercise nutrition​ routines. 

ENERGY REQUIREMENTS

For an active person it is important to always calculate caloric needs based on their individual needs. Most likely this will need to be adjusted depending on their daily activity levels, so the standard daily recommendations should not be used.

Many people find exercise performance and recovery to be highly related to optimal calorie intake to balance their specific energy expenditure.

CARBOHYDRATE REQUIREMENTS

Exercise intensity and duration is a key factor when determining the carbohydrate needs for an active person. Carbohydrates are necessary to replenish and maintain muscle glycogen levels to optimize performance and reduce fatigue.

An effective strategy is a pre, during and post intake of carbohydrates when exercising, again to ensure adequate glycogen levels.

A further benefit to this is the hormonal response, as carbohydrates are potent activators of insulin, thus keeping the body in that anabolic environment, and reducing potential release of catabolic hormones.

PROTEIN REQUIREMENTS

Protein requirements for exercising individuals will be higher that non-exercisers and this is to help boost protein synthesis, reduce recovery time and maintain a positive nitrogen balance.

It is suggested that protein intake be set to 1.5 -2g per kg per day for regular exercisers, with protein sources being of high quality.

FAT REQUIREMENTS

Healthy fats should always have a place in an exerciser’s diet, but less may be required to ensure adequate amounts of protein and carbohydrates are met.

A main benefit of including healthy fats in the diet is to help maintain testosterone levels which may be suppressed during periods of high intensity training.

NUTRIENT TIMING

Nutrient timing may not appear to be as important as we once thought, especially when it comes to improving body composition. However, for the exerciser, nutrient timing can and should have a place.

Programming and timing of adequate dietary ingestion can improve performance and recovery from exercise. The following guidelines are typically used:

This has been considered ‘go-to’ protocol for exercisers who want to enhance energy, anabolism and recovery from their training. 

SUPPLEMENTS

There are a number of supplements that may benefit the exerciser, including:

Essential Amino Acids (EAA's)

The ingestion of EAA mixture before or after training has been shown to provide potential benefits to optimise performance and limit fatigue.

EAA ingestion before and during exercise not only boosts levels of EAA’s in the bloodstream, but helps control increases of free tiytopham, which results in reduction of exercise stress.

It is suggested that 4-12g EAA’s a day while training is the ideal dosage.
Ingesting these with carbohydrates and protein may also improve training adaptations. 

Vitamin C

Vitamin C is a powerful antioxidant that can reduce any issues of immune system suppression from exercise. 

By enhancing the immune system, the exerciser can be sure they are not susceptible to illness or poor health. 

Zinc

Regular exercisers have been reported to experience zinc deficits, supplementation can be used to enhance the immune status of these people.

Zinc has been shown to reduce various cold symptoms and ensure normal metabolism. 

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You now understand the importance of training, its various types and fundamental components.

More importantly, you know how the body can respond to exercise and the nutritional recommendations required to maximise the results from it.