Supplements, creatine and nitrate (wk 9) Flashcards
What do supplements, sports nutrition and everyday nutrition fundamentals?
-Supplements -> potentially boosting performance via strategic use of a small number of nutritional ergogenic aids
-Sports nutrition -> consuming whole foods and fluids before, during and after exercise to promote optimal fueling, hydration and adaptation
-Everyday nutrition fundamentals -> choosing nutritious foods and fluids that support optimal health, fueling and recovery, by aligning energy intake and expenditure
What is a dietary supplement?
-> A product taken by mouth that contains a ‘dietary ingredient’ intended to supplement the diet. They come in many forms: enriched foods (bread), functional foods (smoothies), sports foods (lucozades) and single or multiple nutrient/ mineral foods (multivitamins)
Why do athletes take supplements?
-> Among 310 competitors at the IAAF World Championships 86% consumed supplements. Reasons for using supplements:
* To aid recovery from training (71%)
* For health (52%)
* To improve performance (46%)
* To prevent or treat an illness (40%)
* To compensate for a poor diet (29%)
Other reasons:
* For financial gain (sponsorship) or because products are provided free of charge
* As a ‘just in case’ insurance policy
* Because they know or believe that other athletes/ competitors are using the supplement(s)
Are supplements taken by athletes worth it?
Performance
Health
Insurance policy
Free samples
- Financial
- Health
- Performance
- Drug test failure
What is anti-doping?
-> Anti-doping regulations were developed over many years to promote fairness in sport and to protect the health of the athlete. Strict liability – The offence lies in having a prohibited substance in a sample and Prevalence of positive doping test is typically 1-2% in elite athletes.
What are the risks of supplement use?
- Contamination: poor quality control in manufacturing and storage
-Supplements may contain undeclared prohibited substances, for example, due to poor manufacturing practices resulting in contamination of the raw ingredient or deliberate inclusion of ingredients not listed on the label
-Rates of contamination could be as high as 10-25% of all supplements across Europe and the US, with more recent reports being as high as 38% - Absence or lower than declared levels of ‘actives’
-Often supplements may not contain the actual amount of ingredient stated on the label in the final product, and some do not contain any at all - Presence of undeclared doping agents
-One of the key factors that elite athletes need to consider within the complex world of supplements and sports foods is whether the consumption of these products could lead to an inadvertent case of doping
-IOC research found 15% from 634 non-hormonal nutrition supplements contained undeclared steroids banned by WADA - Harmful to health/ performance
What supplements are used to prevent or treat nutrition deficiencies?
Vitamin D, iron and calcium
What are sports foods that provide a practical form of energy and nutrients?
-> In some situations, it is impractical for an athlete to consume ‘everyday’ or normal foods to meet their nutrition goals due to issues around preparation or storage: training schedules, gut comfort and energy budget:
What is Ron Maughan’s rules of dietary supplements for athletes?
- If it works, it’s probably banned
- If it’s not banned, then it probably doesn’t work
- There may be some exception
What are evidence-based ergogenic aids?
Creatine, nitrate, caffeine, beta-alanine and sodium bicarbonate
What is the FFNFO framework?
In word document
What is creatine?
-> Endogenously synthesised from AA (arginine, glycine and methionine) in the liver, pancreas and kidneys. >95% is stored in skeletal muscle. Approximately 50% obtained from the diet.
What are creatine stores?
-> About two thirds of intramuscular creatine is PCr with the remaining being free creatine. The total creatine pool (PCr +Cr) in the muscle averages about 120mmol/kg dry muscle mass. The upper limit of creatine storage appears to be about 160mmol/kg dry muscle mass. Vegetarians have been reported to have lower intramuscular creatine stores (90-100mmol/kg dm).
What is the creatine turnover?
-Synthesis ~2g/day (1g endogenous and 1g exogenous (diet))
-Excretion ~2g/day (creatine (urine))
-Increasing muscle creatine levels -> Muscle total creatine content for 8 subjects. 4 x 5g (20g) creatine per day for 5 days. Total creatine content increased in all subjects.
What are the effects of creatine?
-> Increase in maximum work and total work done in 30 seconds (isokinetic cycling). Creatine and muscle hypertrophy.
Upper and lower body muscle hypertrophy from creatine:
-Upper body and lower body muscle hypertrophy ->
-The results suggest that creatine supplementation combined with RT promotes a small increase in the direct measures of skeletal muscle hypertrophy in both the upper and lower body.
-What are the effects -> Increased PCr resynthesis = Short-term, high-intensity exercise capacity to perform repeated bouts of high-intensity effort. Brain health – anti-inflammatory and anti-oxidant effects
Creatine metabolism during exercise:
-> PCr levels higher in type II fibres than type I fibres. PCr levels decrease during maximal exercise (because its breakdown sustains high rates of ATP production). PCr can be depleted in ~10 seconds. 80% re-synthesised in ~4 minutes.
Mechanisms of action - supplementation with creatine:
- Increased Cr stores of 30% = increased PCr resynthesis
- Increased muscle glycogen
- Increased growth factor expression
- Increased protein synthesis
- Decreased muscle damage
- Training harder, longer = increased lean mass/ strength
What are creatine sources?
- Diet (red meet (beef pork) and some fish (tuna, salmon, cod, herring) – but not enough
- Creatine monohydrate (CM):
- White powder, 99% absorbed
- Significant amount of evidence
- Better uptake mixed with a carbohydrate containing liquid or food (consume quickly after mixing)
- Synthetic (suitable for vegetarians and vegans)
What are the creatine loading protocols?
-> No acute effect- loading protocols
* Short, high-dose protocol: 20g/day (split in 4 doses) for 5 days and 0.3g/kg BM (split in 3-4 doses) for 5 days
* Long, low dose protocol: 3-5g/day for 20-30 days
* Maintenance dose: 2-5g/ day
* Washout period = 4-6 weeks
When to consider creatine use?
- Single (+1-5%) and repeated bouts (+5-15%) of high-intensity exercise
- High-intensity max efforts <150 sec, largest effects on <30 sec tasks.
- Endurance exercise -> Recent evidence shoes that a combination of creatine and CHO loading may increase power output during repeated high-intensity sprint efforts during the late stages of prolonged stimulated TT cycling
- Concussion -> Improvements in cognitive processing in the brain and potentially reduced damage and enhance recovery from mild traumatic brain injury/ concussion
What is the individual variability of creatine?
- Baseline levels of muscle creatine -> Individuals that have high muscle creatine levels will experience low creatine uptake from supplements, and vice-versa. Therefore, individuals with low muscle creatine levels (e.g. vegetarians) have the greatest potential for increases in response to supplementation
- Sport type -> In sports where performance is not determined by PCr availability (or fast ATP resynthesis) creatine supplementation will likely not have any effects (e.g. ultra-endurance or exclusively skill-based)
What are the concerns for creatine?
- Increase in body mass (1-2kg) -> Likely as a result of water retention. It may be counteractive for the performance for endurance and/or weight-sensitive sports. Consider washout period (4-6 weeks) if using creatine.
- Myths -> There is no evidence that creatine supplementation causes kidney damage, muscle cramps, strains, damage/ injury, or affects fluid balance and heat dissipation
What are the safety issues of creatine?
- No evidence of adverse effects with long term (4 years) creatine supplementation at appropriate dosages in healthy individuals
- Mild, temporary gut upset can occur but can be attenuated with split dose, longer loading protocol and avoidance of high fibre foods with ingestion
- Contamination: all supplements have a doping risk of some kind. Athletes should only use batch-tested supplements.
