Australian Triathlete – July-August 2017

70 | AustrAliAn triAthlete

Training TOOLBOX

PERfoRmAncE

references:

Pinckaers PJ; et al. (Sports Med., 2017). Ketone Bodies

and Exercise Performance: The Next Magic Bullet or

Merely Hype?

Evans M; et al. (J Physiol., 2016). Metabolism of ketone

bodies during exercise and training: physiological basis

for exogenous supplementation.

Holdsworth D; et al. (Med Sci Sp & Ex., 2017).

A Ketone Ester Drink Increases Postexercise Muscle

Glycogen Synthesis in Humans.

Da Silva Barbosa C; et al. (Front. Physiol., 2017).

Effects of Sesame (Sesamum indicum L.)

Supplementation on Creatine Kinase, Lactate

Dehydrogenase, Oxidative Stress Markers, and Aerobic

Capacity in Semi-Professional Soccer Players

Desbrow B; et al. (Appl Physiol Nutr Metab., 2014).

Comparing the rehydration potential of different

milk-based drinks to a carbohydrate-electrolyte

beverage.

Desbrow B; et al. (Int J Sport Nutr Exerc Metab., 2013).

Beer as a sports drink? Manipulating beer’s ingredients

to replace lost fluid.

Desbrow B; et al. (Int J Sport Nutr Exerc Metab., 2015)

Manipulations to the Alcohol and Sodium Content

of Beer for Post-exercise Rehydration.

Dr SIMoN SoSTArIc

PhD.,BAppSc.,AEP.,AES

Exercise Physiologist /

Sport Scientist

Dr Simon Sostaric is a distinguished

exercise physiologist, sports

scientist, researcher and author.

Simon holds a physiology doctorate

(Victoria University, Melbourne,

Australia), in electrolyte regulation

and skeletal muscle fatigue.

He is the founder and director of

Melbourne Sports & Allied Health

Clinic (www.msahc.com.au), with 25

years’ experience in professional

sport, clinical practice and academia.

for more information,

Twitter: @DrSimonSostaric

facebook: @melbournesports

andalliedhealthclinic

Beer

Let’s face it, many athletes have a yearning

for a cold frothy now and then – and don’t

they go down a treat when you’re thirsty!

We have been led to believe that beer,

or any alcoholic beverage for that matter,

should be avoided after exercise.

To elaborate on misconceptions, a series

of experiments were conducted by

Desbrow and colleagues to identify the

merits of beer as a “sports drink”

(2013) and the effects of manipulating

alcohol and sodium content of beer on

post-exercise rehydration (2015).

During the first experiment (2013),

seven males cycled to induce dehydration

(~2% drop in body mass) and then were

assigned to a range of beer compositions

(2.3% low-alcohol; low-alcohol with 25

mM sodium; 4.8% full-strength;

full-strength with 25 mM sodium) on four

separate occasions. The volume and rate

of beverage consumption was the same

as the milk experiment previously

described. The light beer + 25 mM

sodium proved to be the most effective of

the four beverages in enhancing net fluid

balance and lower urine output.

The second series of experiments

(2015) followed identical protocols to the

first series (2013), with additional

manipulation to the alcohol and sodium

content of beverages: low-alcohol with

25 mM sodium; low-alcohol with 50 mM

sodium; 3.5% alcohol mid-strength;

milk-like products. So, how does milk, or

milk-like products, stack up against the

more traditional carbohydrate-electrolyte

beverage as an ideal recovery drink?

To answer this question, Desbrow and

colleagues (2014) subjected 15 males to a

rigorous intermittent cycling protocol,

inducing a 2% loss in body mass.

Participants replenished with a variety of

beverages (cow’s milk, soy milk, Sustagen

milk-based supplement and Powerade

sports drink) on four separate occasions,

at a rate of 150% body weight loss over

one hour. Furthermore, participants were

monitored closely during the four-hour

period after that, via urine, blood, body

mass and subjective feedback analyses.

Following the trials, milk-based

beverages (particularly Sustagen) were

retained at a greater rate than the sports

drink, as was the feeling of satiety. Plasma

volume, electrolytes and thirst rating did

not differ between the treatments.

Therefore, the milk-based beverages

provided a more effective rehydration

outcome than the traditional sports drink.

Furthermore, milk-based beverages

provided superior sources of essential

energy, protein and sodium following

intense exercise.

The only downside to milk based

products for recovery is for those who

dislike milk or have a lactose allergy.

That said, lactose-free alternatives are

readily available and very cheap.

mid-strength with 25 mM sodium. On this

occasion, the light beer with 50 mM

sodium was the most effective in regaining

and retaining exercise-induced fluid loss.

Furthermore, it appears that manipulation

of sodium concentration rather than

alcohol content per se has a greater

impact on fluid retention.

If you like beer, you’re in business. If

your training-induced dehydration is

substantial, let someone else drive!

In the next edition we will focus

attention on a range of wearable

recovery methods.