Runner\'s World UK - 09.2019

HIT THE LOWS

QUICK THINKING

IN FOR THE CHILL

KEEPING YOUR BRAIN chemistry well oiled

could mean you stay one step ahead of heat

exhaustion. ‘Whichever model of fatigue you

believe in, neurotransmitters play a key role,’

says sports scientist Lieselot Decroix. And

when the mercury rises, dopamine is key

among these neurotransmitters. ‘Dopamine

impacts motor behaviour – the movement

of your limbs – and this is especially true in

the heat,’ says Decroix.

Better known as a mood-enhancing feel-

good chemical, dopamine also plays a key

role in the thermoregulatory centre of your

brain. Changes in dopamine concentrations

affect core-temperature regulation during

exercise; and during exercise in temperatures

of 25C or above, performance has been

shown to improve with a dopamine hit.

As dopamine is synthesised in the body,

you can’t simply down a dopamine shot,

but you can eat foods that provide the

nutrient building blocks you need to

produce dopamine. These include the

amino acids L-theanine and tyrosine,

which can both be obtained from protein-

rich foods like lean chicken and tuna. Fish oil

is also beneficial, as is phosphatidylserine,

a phospholipid that is abundant in organ

meats such as chicken hearts and is also

found in fish such as mackerel.

RACE

COOL

GLOW IN THE PARK

31 August

Kempton Park, Middlesex

This family event involves

running, walking and

dancing (with glow sticks)

around two laps of a 2.5km

loop. The 8:30pm start

means the day will have

cooled off considerably.

RUN THE RUNWAY

31 August

Dalcross, Inverness

A run around Inverness

Airport to raise money for

Maggie’s Highlands, which

offers support for people

affected by cancer. North

Scotland’s summer average

is no more than 16C. The

midnight start means it’ll

be even cooler.

BRESSAY PARKRUN

Every Saturday at 9.30am

Bressay, Shetland

Scotland again but this time

the chill is augmented by the

constant breeze. Shetland is

officially the windiest place

in the UK, with an average

wind speed of 14.7 knots.

PRE-RUN COOLING is not

solely about a chill from

within – there are many

methods of reducing

temperature from the

outside. Ice vests have

been used since the 2004

Athens Olympics, but

research on their benefits

is equivocal. A 2004

University of Iceland study

found an 1.1 per cent boost

in 5K performance in hot

conditions (32C) after

wearing an ice vest during

an active warm-up. The

jacket cut core and skin

temperature, as well as

perceived exertion levels,

but only during the early

phase of the run.

Other methods include

taking a cold shower,

spraying wristbands with

anti-freeze and using

menthol. Menthol triggers

thermoreceptors, eliciting

a sensation of coolness

without actual reductions

in body temperature. But

with all pre-cooling

strategies, it’s

worth heeding

a word of

warning from

Mike Tipton,

professor

of human and applied

physiology at Portsmouth

University, who is helping

British athletes prepare

for the heat of Tokyo

Olympics in 2020: ‘If you

pre-cool, your muscle

function will deteriorate.

It can also evoke cold-

induced diuresis [excessive

production of urine]. That’s

because you’re shifting

fluid from the periphery

• because you’re cold – to
  your core. The body senses
  that as overload and you
  produce urine, so you risk
  dehydrating yourself.’

THERE’S A MISCONCEPTION that the

highest temperatures occur at noon, but

peak temperatures are typically later in

the day – around 3pm – as heat

continues to build. That’s important,

says Professor Tipton. ‘A worthwhile

strategy, that’s often used at training

camps, is to play around with the time

of day you train,’ he says. ‘If there’s

a significant rise in

temperature, you just won’t

be able to train like you

normally would in mid-afternoon –

not to start with, anyway.’

That’s why, when looking to maintain

intensity and duration of sessions,

you should train early in the morning

or later in the day. You should then face

the hottest

temperatures but

begin by walking.

‘This is incremental

heat exposure,’ says

Tipton. You then build up to

your normal running during mid-

afternoon over two weeks. Tipton

advises you turn off any air conditioning

during the day because the cooler room

will impair the adaptation you need.

044 RUNNERSWORLD.COM/UK SEPTEMBER 2019