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Total body water

• TBW ~60% of body (45-75%); 65% ICW + 35% ECW

• Trained athletes have relatively high TBW values

– high muscle mass (70-80%) and low body fat (10%)

– higher glycogen reserves (3mL H2O/g glicogénio)

• Regulated within ± 0.2 to 0.5% of body mass

pH, osmolality, temperature, metabolite output

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HYDRATION ASSESSMENT

•3 (> ♀) consecutive morning nude BW measurements after voiding � baseline value

•Acute changes in nude BW during exercise � ~ sweat losses � fluid replacement

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• Drink ~5–7 mL/kg at least 4 h before the exercise

If does not produce urine or the urine is dark or highly concentrated

• Drink another ~3–5 mL/kg about 2 h before the event

Imediatamente antes (?)

• 5mL/kg Burke, 2000

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• Ingerir máxima quantidade sem desconforto para manter perdas <2%

• ↑ vol. início, a intervalos regulares e interromper a 40min do fim

• Sódio: 20-40mmol/L, se Ex >2h ou perdas >3-4g

• Cafeína: 1,5mg/kg nos últimos 40min

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Players at risk of extreme sweat or sodium losses should:

• Increase their dietary salt intake

• During exercise, add extra sodium to fluids (1.5g of salt/L)

• At the first sign of cramps � 3 g salt (½ tsp) in 600 ml of fluid

• Old practices (salt tablets, bananas, pickle juice ??) are not effective

• Plasma [Na+] < 130 mmol/L � headache, vomiting, swollen hands/feet, disorientation (due to

encephalopathy), and wheezy breathing (due to pulmonary edema) … seizure, coma,

respiratory arrest, and death.

• Cause of hyponatremia?

In events <4 h is from overdrinking (intake > sweating rate) of hypotonic fluids

In ultra-endurance events, excessive loss of total body sodium is the primary factor

• At greater risk: smaller and less lean individuals, women, older adults, who run slowly, sweat

less, are less well trained and drink hypotonic fluids heavily

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Athletes must no gain weight during exercise!

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• Will stimulate thirst and glucose absorption, retain fluids, without any detrimental effects on

health, provided that fluid is enough and renal function is not impaired.

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• 48% had iron deficiency (low ferritin levels) without anaemia � ↓ Performance

• Those with iron deficiency had significantly greater calcium intake

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Excessive ROS production

• Sarcolemmal phospholipids peroxidation � muscle damage

• Damage ATPase pumps, muscle contractile and mitochondrial proteins � fatigue

• Promote local inflammation � delayed-onset muscle soreness and recovery

• Oxidative stress adversely affect immune function

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Salmão selvagem 500-1000 UI/100g, cativeiro 100-250 UI/100g Chen, 2007

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Skin pigmentation

Age

Time of the day

Season

Latitude

Smog/cloud

Sunscreen use

Time outdoor

…

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20-40 ng/mL

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Injuried football players had lower vit D levels than uninjuried Shindle, 2011

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5.000IU/d for 8 weeks

29 � 103 nmol/L

• Athletes may require 800-7000 IU/d to achieve optimal status.

• Higher: indoor sports, darker skin, adiposity, live/train > 35-37º, extensive clothing and use sunblock.

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• Nausea

• Vomiting

• Poor appetite

• Constipation

• Weakness

• Weight loss

• Mental confusion

• Cardiac rhythm irregularities

• Calcification of soft tissues

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1. If you were offered a banned performance-enhancing substance that guaranteed that

you would win an Olympic medal and you could not be caught, would you take it?

2. Would you take a banned performance-enhancing drug with a guarantee that you will not

be caught, you will win every competition for the next 5 years, but will then die from adverse

effects of the substance?

98%

> 50%

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Cafeína

• Redução da percepção de esforço• Maior recrutamento de unidades motoras

• Ergogenic at low doses 3mg/kg Graham et al 1995

• Reduces perception of fatigue, enhances central drive Graham et al 2004

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Creatina

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300mg/kg + água (>0,5L), 1 ou 2 h antes do exercício

600mg/kg repartido em várias tomas durante o dia

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• Bicarbonato• Citrato• Beta-alanina• Carnosina

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Maughan’s Rules of Dietary Supplements

1. If it works, it’s probably banned

2. If it’s not banned, then it probably doesn’t work

3. There may be some exceptions