Scaling Your Diet with Training Intensity: A Practical Blueprint

Aligning Nutrition With Training Intensity: Part 2

Knowing approximately how much protein, carbohydrate and energy your body requires is one thing. Translating that into an ordinary training week is rather more complicated, particularly when the demands of one session bear little resemblance to those of the next.

A useful starting point is to match food intake to the actual work being performed, while accounting for what comes afterwards. Someone completing a long endurance session may need substantially more carbohydrate than they would on an easier day, whereas a person performing a relatively short strength session may have little reason to make dramatic changes. Protein can often remain reasonably consistent, and fluid or electrolyte requirements should reflect the duration, environment and amount of sweating involved.

The complication is that people rarely train in neat, predictable categories. A week's training might involve heavy lifting on Monday, a conditioning session on Tuesday, a lighter Wednesday, followed by another demanding session on Thursday. There may be an important event at the weekend, or a period of reduced training while someone recovers from illness or accumulated fatigue.

It wouldn't be especially useful to prescribe the same food intake for every situation, but neither is there much sense in constantly adjusting calories and macronutrients without knowing whether those adjustments are necessary.

In Part 1, Fundamental Diet Principles & Why They Matter More as You Train Harder, I examined energy availability, protein requirements, carbohydrates, fats, nutrient timing, hydration and micronutrient adequacy. This second article looks at how those principles can be applied, including carbohydrate periodisation, recovery between sessions, refeeds, competition fuelling and the place of supplements within a training programme.

I'll also work through four different athlete profiles. The figures are illustrative rather than individual prescriptions, but they should make it easier to understand why one approach might be appropriate for a particular training schedule and less suitable for another.

Looking at the training week before changing the diet

The first thing I'd want to know is what the person actually does across the week.

Training intensity is part of that assessment, but duration, total workload, frequency and recovery time can be equally important. A brief strength session involving heavy loads might be demanding without using anything like the amount of energy required for a two-hour run. An apparently easy endurance session can still represent a substantial nutritional demand if it lasts long enough.

The programme's purpose also needs considering. Someone trying to maintain strength while reducing body weight has a different set of priorities from someone preparing for a long-distance event or attempting to gain muscle.

I would begin with a few practical questions. How many hours are spent training? How much of that work relies heavily on carbohydrate? Are there several demanding sessions close together? Is body weight changing intentionally or unintentionally? Is the current diet adequate, and are there signs that recovery is becoming difficult?

There is also the question of what happens outside training. Physically demanding employment, poor sleep, travel, stress and a reduced appetite can all make the nutritional side of a programme harder to manage.

Our discussion of personalising supplements and nutrition explores individual circumstances more broadly. I wouldn't interpret personalisation as a need for elaborate testing or detailed calculations in every case, though. Often, the useful information is already available from the person's training schedule, usual eating habits and response over several weeks.

Once those are understood, there may be a reason to adjust food intake. Sometimes there won't be.

Adjusting carbohydrate intake to training demand

Carbohydrate periodisation involves arranging carbohydrate availability around the requirements of training. In practice, this may mean eating more carbohydrate before and after particularly demanding sessions, during prolonged exercise, or on days when the total workload is substantially higher.

It's often described as carb cycling, although I think the term can sometimes make a fairly straightforward nutritional decision sound more complicated than it is.

The scientific rationale comes principally from the relationship between carbohydrate availability, muscle glycogen and exercise performance. Glycogen is an important fuel during prolonged and repeated high-intensity exercise, and depleted stores can become limiting under certain conditions.

Research reviewed by Burke and colleagues supports adjusting carbohydrate intake according to the amount and type of exercise being performed, particularly in endurance sport. But the evidence doesn't suggest that everyone benefits from following a fixed pattern of high-, moderate- and low-carbohydrate days.

A person lifting weights three times a week may be adequately fuelled by a relatively consistent diet. An endurance athlete completing long sessions or training twice in one day may have a stronger reason to plan carbohydrate intake around particular sessions.

The distinction becomes clearer when we consider three common situations.

Easier and recovery days

A rest day usually involves less exercise-related energy expenditure, but it isn't necessarily a day of low nutritional demand.

Muscle repair, adaptation and restoration of glycogen stores continue between sessions. The food eaten on a rest day may also be important preparation for the following day's training.

An athlete who has completed a long endurance session on Saturday and plans another substantial session on Monday may have little reason to reduce carbohydrate dramatically on Sunday. The day between sessions provides an opportunity to recover and prepare.

Someone who is training less frequently, however, may find that their ordinary diet comfortably covers recovery without deliberately increasing carbohydrate intake.

For a person trying to reduce body weight, a modest difference in energy intake between more and less active days may be practical. But there is no requirement to make rest days low-carbohydrate, nor is there reliable evidence that everyone should shift their fat intake to a particular percentage on those days.

Food quality also shouldn't be reserved for rest days. Vegetables, fruit, whole grains, suitable protein sources and dietary fats are relevant throughout the week.

A lower-output day might include eggs and toast for breakfast, salmon with potatoes and vegetables at lunch, and a chicken or lentil-based evening meal. The portion sizes would depend on energy requirements, the preceding session and what is planned next.

Ordinary training days

For many people performing regular resistance training, recreational sport or moderate conditioning, the most practical approach is to maintain adequate daily intake and make relatively small adjustments around training.

Someone who trains after work might eat a substantial lunch, have a carbohydrate-containing snack before the session if needed, and eat an ordinary evening meal afterwards.

There is no particular advantage in forcing carbohydrate into a narrow window if the overall diet is already adequate. Meal timing becomes more relevant when the session is demanding, the person hasn't eaten for several hours or there is limited time to recover before the next workout.

For shorter sessions, specialised carbohydrate drinks may be unnecessary. A banana, toast, yoghurt, rice, potatoes or another familiar food may be sufficient.

The choice depends partly on digestive tolerance, which deserves more attention than it often receives. A large meal containing substantial amounts of fat and fibre may be perfectly nutritious but uncomfortable shortly before intense exercise.

Long, demanding or closely spaced sessions

This is where more deliberate carbohydrate planning becomes useful.

Consider someone completing a prolonged endurance session, several hours of team sport or two demanding sessions within the same day. They may need to think about carbohydrate intake before exercise, fuel during the session and the time available for recovery afterwards.

Sports-nutrition guidance commonly describes daily carbohydrate ranges of approximately 5–7 g/kg for moderate training loads and 6–10 g/kg for higher-volume endurance training, with larger amounts sometimes appropriate for extreme workloads.

These ranges were developed around particular exercise demands. They shouldn't be assigned automatically to anyone whose workout feels intense.

For example, a 90 kg powerlifter completing a relatively short strength session doesn't necessarily require the same carbohydrate intake per kilogram as a 60 kg endurance athlete running for several hours.

During prolonged exercise, carbohydrate intake can also become valuable. Guidance frequently discusses approximately 30–60 g per hour for endurance exercise lasting around one to two-and-a-half hours, with higher rates potentially useful for longer events when suitably practised and tolerated.

These are general sports-nutrition recommendations, not targets for every workout.

Athletes undertaking prolonged exercise should practise their fuelling approach during training rather than introduce large amounts of carbohydrate for the first time on competition day. Gastrointestinal tolerance can be limiting, particularly when exercise is demanding.

For a more detailed look at the relationship between fluid, sodium and carbohydrate during exercise, see our hydration guide for endurance athletes.

Protein and energy intake across the training week

Carbohydrates may be the nutrient most obviously adjusted around particular sessions, but they shouldn't be considered independently of total energy and protein intake.

Protein requirements are influenced by factors including training type, body mass, energy intake and the objective of the programme. The International Society of Sports Nutrition identifies approximately 1.4–2.0 g/kg per day as generally sufficient for most exercising individuals seeking to maintain or develop muscle.

It can be useful to maintain a relatively consistent protein intake through the week, particularly when resistance training is involved. Muscle adaptation isn't confined to the hours immediately after a session, and recovery continues on days without training.

That doesn't mean protein intake must be identical every day or that a precise target should be pursued regardless of the circumstances. The objective is to achieve an adequate overall intake.

Energy requirements are more difficult to estimate accurately without information about the individual. Body weight alone tells us very little about total daily expenditure, and two athletes of the same weight may have considerably different requirements.

This is especially relevant during weight loss.

Someone can meet a protein target while consuming insufficient total energy for their training programme. Higher protein intake doesn't remove every consequence of prolonged or severe low energy availability.

The International Olympic Committee's 2023 consensus statement on Relative Energy Deficiency in Sport describes the potential effects of problematic low energy availability on health and performance. These effects are complex, vary between individuals and cannot be diagnosed solely from a calorie calculation.

I would therefore be cautious about making repeated reductions in food intake simply because body weight isn't changing as quickly as expected. Weight fluctuations can also reflect glycogen, associated water, digestive contents and other factors.

Our guide to making weight, fat loss and performance risk examines some of these problems in greater detail, particularly for athletes competing in weight categories.

Planning food around training and recovery

Once overall intake is appropriate, meal timing can be adjusted where it offers a practical advantage.

For someone completing one session per day, an ordinary meal containing carbohydrate and protein beforehand, followed by a normal meal afterwards, may be sufficient. The exact timing depends on what they've already eaten, the size of the meal and individual digestive tolerance.

Someone completing a demanding session in the morning and another in the afternoon has less time to replenish glycogen. Under those circumstances, carbohydrate intake soon after the first session can become more relevant, alongside sufficient protein and fluids.

Research-based recommendations for rapid glycogen restoration can involve carbohydrate intakes around 1.0–1.2 g/kg per hour during the early recovery period when the next glycogen-demanding session is only a few hours away. This is a specialist strategy for restricted recovery windows, not a general requirement after every gym session.

Protein can be distributed across the day through ordinary meals, with a protein powder used where it makes meeting requirements easier. A supplement doesn't need to be part of every training session, and it's worth remembering that more complicated timing doesn't necessarily compensate for inadequate total intake.

Hydration also depends on the circumstances.

Longer sessions, hot conditions and substantial sweating can justify more deliberate fluid and sodium replacement. Sodium is generally the principal electrolyte lost in sweat, although concentrations differ between individuals.

For shorter sessions in cooler conditions, ordinary meals and water may be enough.

It is possible to overdrink, particularly during prolonged exercise. Excessive fluid consumption can contribute to exercise-associated hyponatraemia, so attempting to replace every possible millilitre without considering individual requirements isn't a sensible strategy.

I've explored the composition of sweat separately in What Electrolytes Do You Lose in Sweat?.

Carbohydrate loading, refeeds and diet breaks

These strategies are frequently discussed together, but they serve different purposes and shouldn't be treated as interchangeable.

Carbohydrate loading

Formal carbohydrate loading aims to increase muscle glycogen stores before events where carbohydrate availability may limit performance.

The strongest evidence concerns prolonged endurance exercise, particularly events lasting substantially longer than 90 minutes. Athletes preparing for such events may use several days of higher carbohydrate intake, often alongside reduced training volume.

Established sports-nutrition guidance commonly describes approximately 10–12 g/kg per day for 36–48 hours before certain prolonged endurance events, although the protocol, practicality and individual tolerance require consideration.

These quantities are substantial. A 60 kg athlete consuming 10 g/kg would be eating 600 grams of carbohydrate per day, which may require deliberate planning and can be difficult to tolerate.

That doesn't make aggressive carbohydrate loading appropriate for every competition.

A powerlifting meet, for example, can involve a long day of warm-ups and attempts, but the evidence supporting formal endurance-style carbohydrate loading cannot simply be transferred to maximal strength performance. Arriving adequately fed, avoiding prolonged periods without food and maintaining comfortable hydration are more defensible priorities.

An athlete with several bouts or events across a day may have different requirements again, particularly when repeated efforts and recovery intervals are involved.

Food tolerance matters throughout. Athletes sometimes prefer lower-fibre carbohydrate sources before competition because large amounts of fibre, fat or unfamiliar foods can cause gastrointestinal discomfort.

For anyone new to carbohydrate loading, the approach should be evaluated during training before being considered for an important event.

Refeeds during a dieting phase

A refeed is generally understood as a planned, temporary increase in food intake during a period of energy restriction, often achieved by increasing carbohydrate.

It may provide additional carbohydrate availability around demanding sessions and can make an otherwise restrictive diet easier to manage for some individuals.

There is also research examining whether intermittent periods of higher intake help preserve fat-free mass, resting metabolic rate or dietary adherence during weight loss. Results are mixed, and the available studies differ in their populations and protocols.

One trial in resistance-trained participants reported favourable outcomes for certain measures of lean mass and resting metabolic rate during a specific intermittent carbohydrate-refeeding protocol. Other research has found less compelling differences between intermittent and continuous restriction.

I wouldn't conclude that a refeed reliably restores metabolic rate, prevents hormonal adaptation or produces faster fat loss.

Leptin, thyroid hormones and other components of energy regulation respond to changes in energy balance, but temporary shifts in hormone concentrations shouldn't be confused with proven improvements in long-term health or body composition.

A refeed might be useful for someone following a prolonged dieting programme, particularly if it allows a demanding session to be fuelled more adequately or improves dietary adherence. Equally, someone may prefer a smaller, consistent deficit without planned high-intake days.

There is no universal requirement to schedule one or two refeeds every week or to eat a fixed percentage above maintenance.

Diet breaks

Diet breaks usually involve a longer planned period at or around estimated energy maintenance rather than a single higher-carbohydrate day.

They may be considered when dietary restriction has continued for some time, particularly where adherence, training quality or psychological fatigue becomes difficult to manage.

The research doesn't establish that diet breaks are universally superior to continuous dieting for body-composition outcomes. They can, however, offer an alternative way of organising a longer weight-management programme.

Someone showing signs of problematic low energy availability, menstrual disruption or other health concerns shouldn't treat a refeed or diet break as a substitute for assessment by an appropriately qualified healthcare professional.

For readers interested in why individual responses differ, our article on biochemical individuality explores variation in nutritional responses. I would still be cautious about using individual variation to justify strategies unsupported by good clinical evidence.

Individual considerations, including menstrual health

Nutrition planning also needs to account for circumstances that aren't visible from an athlete's body weight or training schedule.

Digestive tolerance, dietary restrictions, medical conditions, sleep patterns and previous experiences with dieting can influence whether a particular approach is realistic.

Menstrual health is another important consideration.

Hormonal fluctuations during the menstrual cycle are well established, and some individuals experience changes in appetite, gastrointestinal comfort, sleep, temperature regulation and perceived exercise performance.

The evidence for prescribing a particular carbohydrate intake, sodium target or training programme according to menstrual-cycle phase is much less certain.

Research is complicated by differences between participants, hormonal contraceptive use, the methods used to confirm cycle phases and substantial variation in symptoms. The available evidence doesn't justify instructing all women to reduce carbohydrates during the follicular phase or increase sodium during the luteal phase.

I'd be more interested in identifying individual patterns. If an athlete repeatedly experiences greater hunger, digestive discomfort or difficulty sleeping at particular times, it may be useful to consider how their meals and training are arranged.

That doesn't require assuming the menstrual cycle follows an identical 28-day pattern for everyone, or that a particular phase automatically determines nutritional requirements.

Irregular or absent menstrual periods deserve particular attention. They can be associated with problematic low energy availability, but they also have other potential causes.

An athlete experiencing these symptoms should seek medical assessment rather than attempting to correct them through carbohydrate cycling, refeeds or supplements alone.

The same general caution applies to persistent fatigue, recurrent illness, unexpectedly poor recovery and other symptoms that may have nutritional or non-nutritional explanations.

Four practical athlete examples

The following examples are hypothetical. They aren't calculated from individual energy-expenditure assessments, and the calorie figures shouldn't be interpreted as recommendations for people of the same body weight.

I've included them to demonstrate how nutritional choices might change with the training programme, while keeping protein intake, total energy and the use of supplements in perspective.

The calculations use the standard approximate energy values of 4 kcal/g for carbohydrate and protein and 9 kcal/g for fat. Actual food-label energy values and individual requirements can differ.

Tom: 80 kg recreational lifter reducing body fat

Tom performs four resistance-training sessions each week. His aim is to reduce body fat gradually while maintaining training quality and as much lean tissue as possible.

Before changing his diet, I'd want to know how his body weight has been trending, what his current intake looks like and whether the proposed deficit is compatible with his training.

For illustration, assume his observed energy expenditure allows a moderate deficit at the following intake.

	Demanding training day	Easier day
Carbohydrate	300 g	180 g
Protein	160 g	160 g
Fat	80 g	80 g
Calculated energy	2,560 kcal	2,080 kcal

These totals are mathematically consistent. They don't prove that either calorie target is suitable for Tom.

The higher-carbohydrate day might be useful around a longer resistance session or one involving additional conditioning. On an easier day, less carbohydrate might be practical if his following sessions are appropriately fuelled.

There would be little reason to reduce protein automatically on rest days, particularly while dieting. I'd also want to ensure the overall weekly deficit isn't unnecessarily large.

Where supplementation might fit

Creatine monohydrate has a substantial evidence base in repeated high-intensity exercise and resistance-training contexts. For Tom, it may be worth considering alongside a suitable training programme, with attention to current UK marketing rules and product suitability.

Protein powder could also be convenient if he struggles to obtain adequate protein through ordinary meals.

A One Life Foods magnesium product, such as Magnesium Bisglycinate, might be considered where dietary magnesium intake is insufficient. That is different from suggesting it will automatically improve sleep or accelerate recovery.

Similarly, Elevate D3 would be considered in the context of vitamin D intake and established UK public-health guidance, rather than as a general muscle-building product.

I wouldn't automatically add LUNA, oyster extract and several other products simply because he's dieting. Each additional supplement should have a clear reason for being there.

For a wider discussion of the strength of evidence behind different ingredients, see The Most Researched Natural Supplements.

Sara: 60 kg endurance athlete with varying training loads

Sara trains five or six days each week, combining shorter easy runs, an interval session and a progressively longer weekend run.

Her nutritional demands won't be the same every day, particularly when her longer runs increase in duration.

For illustration, assume that her estimated and subsequently monitored requirements support the following intake on two different types of day.

	Long training day	Easier day
Carbohydrate	430 g	280 g
Protein	110 g	110 g
Fat	70 g	75 g
Calculated energy	2,790 kcal	2,235 kcal

On the longer training day, the example provides approximately 7.2 g/kg of carbohydrate. That may be reasonable for a sufficiently demanding endurance workload, but it would be excessive to prescribe automatically to someone running for only a short period.

I'd examine how much time Sara spends running, whether she's fuelling during longer sessions, how comfortably she tolerates carbohydrate and whether her body weight and recovery suggest adequate energy availability.

The easier-day intake remains substantial because lower training demand doesn't eliminate recovery needs. It may also precede another important session.

Where supplementation might fit

For prolonged endurance exercise, a carbohydrate drink can be useful when carrying or eating solid food is impractical. The amount would depend on the session duration and her gut tolerance.

An electrolyte product may also be relevant in hot conditions or where substantial sodium losses occur, although the actual sodium content and serving size need checking.

One Life Foods' Vitality or VITA products could be considered as multivitamin options if her diet or circumstances justify supplementation, but a multivitamin isn't a substitute for sufficient food intake.

Elevate D3 may be relevant in light of UK vitamin D guidance.

Iron deserves particular care in endurance athletes, but suspected low iron status should be assessed appropriately rather than treated by adding a product without testing or professional advice.

I wouldn't include Lion's Mane automatically as a cognitive-performance supplement. The evidence for specific cognitive outcomes remains dependent on the preparation, population and study design, and shouldn't be converted into an unsupported commercial claim.

For Sara, proper fuelling, energy availability and recovery are likely to be more useful starting points than assembling a large supplement routine.

Jess: 65 kg CrossFit athlete in a cutting phase

Jess undertakes several resistance and conditioning sessions each week. She wants to reduce body fat without making her training unnecessarily difficult.

That combination deserves attention because frequent high-intensity exercise and a prolonged energy deficit can become difficult to manage together.

Assume the following two illustrative days fall within a carefully monitored programme.

	Higher-output day	Lower-output day
Carbohydrate	260 g	190 g
Protein	130 g	130 g
Fat	65 g	70 g
Calculated energy	2,145 kcal	1,910 kcal

These are not automatically suitable calorie targets for a 65 kg athlete. Their appropriateness depends on energy expenditure, health, body-composition goals and other personal circumstances.

The higher-output day contains more carbohydrate, while protein remains relatively consistent. On days involving longer conditioning sessions, adequate carbohydrate availability may be particularly important.

If her recovery becomes persistently poor, menstrual cycles change or fatigue increases, I wouldn't assume the solution is simply better carbohydrate timing. The size and duration of the energy deficit, overall training load and possible medical issues need reviewing.

Where supplementation might fit

A protein powder may be useful if her ordinary meals don't provide sufficient protein. Creatine may also be considered where appropriate, although its potential effects on body mass through changes in muscle creatine and water content deserve explanation during a cutting phase.

The original article included PYRO, a stimulant-containing One Life Foods product. I'd retain it as a possible product category to discuss rather than a routine recommendation.

If Jess is considering a stimulant-containing supplement, I'd check the current formulation, total caffeine and other stimulant exposure, label warnings, medication interactions and suitability for her individual circumstances.

Caffeine can influence alertness and exercise performance under certain conditions, but no stimulant can replace adequate energy intake or sleep. There is also no reason to assume a product marketed as thermogenic will produce meaningful or sustained fat loss.

Similarly, LUNA shouldn't be presented as a necessary evening recovery supplement without confirming its formulation and the basis for any product-specific claims.

Sometimes a smaller, simpler routine is more appropriate.

For further discussion, see How to Stack Supplements Properly.

Markus: 90 kg powerlifter seeking gradual lean-mass gains

Markus trains four days per week, with relatively heavy lifting sessions and occasional additional conditioning. His goal is to increase muscle mass while limiting unnecessary fat gain.

His requirements could be relatively high because of body size, overall activity and his intended rate of weight gain, although those factors alone don't establish a precise calorie target.

The following figures are hypothetical examples of two types of day.

	Training day	Easier day
Carbohydrate	500 g	360 g
Protein	180 g	180 g
Fat	100 g	110 g
Calculated energy	3,620 kcal	3,150 kcal

The protein intake is approximately 2.0 g/kg, within commonly used sports-nutrition ranges.

Carbohydrate intake is higher on the training day, but this isn't a recommendation that all powerlifters need 500 grams of carbohydrate. Markus's actual needs would depend on his training volume, current expenditure, digestion and changes in body weight.

If he were gaining weight faster than intended, I'd review total intake rather than assume that one macronutrient was responsible. If weight and performance weren't progressing, I'd first examine his actual energy intake, programme and recovery.

Where supplementation might fit

Creatine monohydrate has an established role in sports-nutrition research relevant to strength and repeated high-intensity exercise.

Protein powder may be useful when larger daily food requirements are difficult to meet comfortably.

One Life Foods' FUEL could be considered as an example of a pre-workout product, provided its current ingredients, stimulant content and label restrictions have been checked. It shouldn't be represented as necessary for muscle growth or guaranteed to improve strength or concentration.

I would also be cautious about combining multiple caffeine-containing products, particularly when coffee, energy drinks and other stimulants are already part of the routine.

Oyster extract, multivitamins and fish-oil supplements shouldn't be included automatically. Whether they offer a useful contribution depends on actual nutritional needs, ingredient composition and the evidence supporting their intended use.

For broader sourcing and formulation considerations, see our article on why trustworthy supplement suppliers can be difficult to identify.

Putting the week together

The four examples illustrate why the same nutritional strategy may produce different results in different settings.

Tom's main concern is maintaining an appropriate deficit without compromising training unnecessarily. Sara has to consider prolonged carbohydrate demands and recovery between endurance sessions. Jess needs to balance a weight-management goal with frequent demanding exercise, while Markus may have relatively high energy requirements without necessarily needing elaborate day-to-day changes.

In each case, I'd begin with the training programme, usual food intake and intended outcome.

A practical weekly review might look like this:

Training situation	What I'd review first	Possible adjustment
Shorter resistance-training session	Daily energy and protein adequacy	Normal meals may be sufficient
Long endurance session	Duration, carbohydrate availability and fluid losses	Plan carbohydrate and fluids before and during exercise
Two demanding sessions close together	Recovery time and glycogen demands	More deliberate carbohydrate intake between sessions
Easier day before an important session	Recovery from previous training and next-day requirements	Maintain adequate fuelling rather than automatically restricting carbohydrate
Training during weight loss	Size of deficit, training quality and health	Adjust energy intake or workload where appropriate

The aim isn't to create a more complicated diet simply because a programme has become more structured.

I'd rather make one or two changes that address a recognisable problem and then assess the response over time.

If someone introduces a higher carbohydrate intake, changes their protein target, begins several supplements and adjusts their training schedule at the same time, it becomes difficult to know which intervention was responsible for any improvement or deterioration.

There is value in being systematic, but the number of variables should remain manageable.

Where supplements fit into a practical plan

As a supplement retailer, I think it's important for One Life Foods to discuss supplementation openly rather than treating it as an inconvenient subject.

But there is a distinction between explaining when a supplement may be useful and presenting a product as the answer to a physiological problem that hasn't been properly identified.

The strongest starting point is to consider the function of the ingredient, the form and quantity supplied, the relevance of the evidence and the person's actual dietary intake.

Protein powders can offer a practical source of dietary protein. Carbohydrate powders can make fuelling prolonged exercise easier. Creatine has a substantial research literature in relevant exercise contexts. Vitamin D supplements may be appropriate under UK public-health guidance.

Electrolyte products should be assessed according to their composition, especially when they're being considered in relation to sweat losses. A product containing a small amount of sodium isn't necessarily suited to the same circumstances as one formulated with a larger sodium contribution.

Other supplements require more individual consideration. It's worth examining whether the evidence applies to the exact ingredient and preparation, whether an authorised health claim exists where required, and whether the supplement adds anything useful to the existing diet.

Our article on why supplements can take time to work looks at some of these questions, although a delayed effect shouldn't be assumed merely because an ingredient is marketed for long-term use.

The temptation to combine multiple products is understandable, particularly when each is presented as addressing a different aspect of performance, wellbeing or recovery. But combining several ingredients doesn't necessarily mean their proposed effects will be additive, and it may introduce overlapping doses or interactions.

I've explored this separately in our guide to stacking supplements, and in getting the most from One Life Foods supplements.

I'd also be careful about relying on stimulants to compensate for fatigue. Caffeine has a legitimate place in exercise research, but persistent tiredness deserves more attention than simply increasing the dose of a pre-workout.

Where a supplement is appropriate, its value should be considered in relation to the rest of the programme. There is little reason to expect a complicated routine to compensate for insufficient energy, inadequate sleep or an unsuitable training load.

Final thoughts

Nutrition doesn't need to change dramatically every time a training programme becomes more demanding. Sometimes the current diet already provides enough energy and nutrients, and there is no particular advantage in manipulating macronutrients from one day to the next.

Other circumstances deserve more attention. Prolonged endurance training, multiple sessions in a day, restricted recovery periods and weight-management phases can all make the relationship between training and food intake more consequential.

Carbohydrate periodisation can be useful when there is a clear reason to adjust availability. Refeeds and diet breaks may have practical applications during certain dieting programmes, but they shouldn't be presented as hormonal resets. Formal carbohydrate loading has its strongest evidence in prolonged endurance sport and shouldn't automatically become part of every competition preparation plan.

The same principle applies to supplements. Some ingredients have good evidence in clearly defined contexts, some provide convenience rather than a unique physiological advantage, and others remain much less certain than marketing often suggests.

I would begin with the training itself, establish whether the diet is adequate and make adjustments that can be explained and evaluated.

The objective isn't to create the most elaborate nutritional programme. It's to arrive at training adequately prepared, recover sufficiently to repeat the work and make progress without compromising health.

For me, that remains a more useful measure of a good nutrition strategy than the number of supplements, meal timings or individual targets it contains.

Research and further reading

1. Mountjoy M, et al. (2023). 2023 International Olympic Committee's consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine, 57, 1073–1097. https://doi.org/10.1136/bjsports-2023-106994

2. Jäger R, et al. (2017). International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition, 14, 20. https://doi.org/10.1186/s12970-017-0177-8

3. Thomas DT, Erdman KA, Burke LM. (2016). Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. Journal of the Academy of Nutrition and Dietetics, 116, 501–528. https://doi.org/10.1016/j.jand.2015.12.006

4. Burke LM, Hawley JA, Wong SHS, Jeukendrup AE. (2011). Carbohydrates for training and competition. Journal of Sports Sciences, 29(S1), S17–S27. https://doi.org/10.1080/02640414.2011.585473

5. Sawka MN, et al. (2007). American College of Sports Medicine position stand: Exercise and fluid replacement. Medicine & Science in Sports & Exercise, 39, 377–390. https://doi.org/10.1249/mss.0b013e31802ca597

6. International Society of Sports Nutrition. Position stands and reviews on creatine supplementation and exercise performance. Consult the published position statements for the populations, protocols and findings relevant to individual use.

7. NHS. Vitamin D: Vitamins and minerals. https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/

Written by

Chris Simon  (Founder, One Life Foods)

Chris has worked in the supplement industry since 2009, with a particular interest in ingredient sourcing, product quality and formulation. Through One Life Foods, he aims to make supplement information more transparent and evidence-led, particularly where scientific findings are frequently simplified in marketing.

Read more about Chris and One Life Foods.

Disclaimer

This article provides general educational information about sports nutrition and isn't individual medical or dietary advice. The examples are hypothetical and shouldn't be used as personal diet prescriptions. Nutritional requirements vary according to training demands, age, health status and other circumstances. Anyone experiencing persistent fatigue, unexplained symptoms, suspected deficiencies, menstrual disturbances or concerns about restrictive eating should seek advice from an appropriately qualified healthcare professional or registered dietitian. Before using a supplement, check its current ingredients, directions, suitability and any relevant medical considerations. Food supplements shouldn't be used as a substitute for a varied, balanced diet and healthy lifestyle.