Faculty of

Health Sciences

Section Sports Medicine

Prof Christa Janse van RensburgRheumatologist & Sports Physician

MD MMed MSc MBChBFACSM FFIMS

MEDICAL CHALLENGES:

EFFECTS of TRAVEL FATIGUE and JET LAG

IOC ATPC 2017Turkey

• International & National Travel:

= lifestyle for elite athletes disruption of regular routine, preparation concerns, competition anxiety, etc.

• Factors that come into play

1. Substantial environmental changes

2. Disruption of the body’s circadian timing mechanisms

3. Travel fatigue / travel stress / jet lag

• Potential mechanisms of impact on performance

• Management

INTRODUCTION Charles H. Samuels. Jet Lag and Travel Fatigue: A Comprehensive Management Plan for Sport Medicine Physicians and High-Performance Support Teams. Clin J Sport Med, 2012, 22(3): 268-273

Covered by Olaf Schumacher

1. ENVIRONMENTAL CHANGES

2. CIRCADIAN RHYTHM SHIFTS

• Loss of synchrony occurs between internal circadian rhythms, e.g. body temperature, and 24h light-dark cycle

• For every 15° travelled (i.e. 1 time zone) the body's biological clock has to move 1 hour into a new time zone

• To adapt & resynchronise completely

± 1 day / time zone crossed

• Direction of travel influences the severity (east vs. west)

• Physiological adjustments occur (superchiasmatic nucleus)

• Endogenous circadian rhythms = relatively slow to adjust

CIRCADIAN RHYTHM SHIFTS

The light-dark cycle seems to be the strongest influence

Purpose of body clock

Ensure physical & mental state

Active day Sleep at night

John Hogenesch from the University of Pennsylvania estimates around 50% of the mammalian genome cycle is under circadian control

2017 Nobel Prize WinnersMichael RosbashMichael W. Young

Jeffrey HallPioneering discovery that our circadian clocks are

regulated by a small group of genes working at the

individual cell level

3. TRAVEL FATIGUE & JET-LAG

Controllable factors

• Journey anxiety

• Nutrition

• Hydration

(extra 15-20ml for each hour in flight)

• Time of sleep

• Body temperature

• Movement / activity

Uncontrollable factors

• Passenger next to you

• Confined space

• Length of flight

• Crossing time zones

• Altitude changes

• Air pressure fluctuations

• Stopovers /Delays

• TurbulenceReilly T et al. Nutrition for travel. Jnl Sports Sc, 2007, 25(S1): S125-134

Greenleaf J, et al. Airline chair-rest deconditioning: Induction of immobilisation thromboemboli. Sports Med, 2004, 34(11): 705-725

Travel fatigue Jet lagDefinition Temporary exhaustion, tiredness Temporary disorder / desynchronosis

Mechanism / Cause

Associated with any long journey(irrespective of mode of transport)

Rapid long-distance, trans-meridian travel

Flight’s direction > length

Direction of travel

N SSeasonal change

e.g. Depart from JHB at 30°C, disembark in Frankfurt at 0°C

W E 2 time zones in any direction

W EShift in local time

e.g. Depart 10h00 from London, arrive 13h00 in NY (watch indicating London time 18h00)

= 8-hour flight across 5 time zones

3 time zones in directions E-W / W-E

Body`s daily rhythms out of sync with destination time zone

Travel fatigue Jet lag

Duration • Subsides next day / after shower /

night’s sleep

• Quicker overcome BUT can

accumulate over course of season

• Can be persistent & impact athlete’s

capacity to recover & perform

• Lasts several days to weeks

• Resolves with resynchronisation

• 1 day/time zone

Severity • Vast inter- & intra-individual variations

• Frequency of trips & length of season play a role

Travel fatigue Jet lag

Characteristics • Cumulative

• Persistent fatigue

• Recurrent illness

• Behaviour and mood

changes

• Loss of motivation

• Episodic

• Intermittent fatigue

• Impaired concentration

• Sleep disturbance (daytime sleepiness,

intermittent fatigue, sleep deprivation)

• GIT disturbance (indigestion, diarrhoea,

constipation)

NB!Travel:

• Direction• Distance• Frequency

Length of season

Eastward Westward

Phase shift

Body clock cycle

• Advance (!!only if

POTENTIAL MECHANISM OF IMPACT

Peter M. Fowler. Performance Recovery Following Long-haul International Travel in Team Sport Athletes. Sports Medicine Journal. www.Aspetar.Com/Journal p.502-509

Schwellnus M, Derman W, Page T, Lambert M, Readhead C, Roberts C, et al. Illness during the 2010 Super 14 Rugby Union tournament–a prospective study involving 22 676 player days. BJSM, 2012;46(7):499-504

http://www.aspetar.com/Journal

Non-Pharmacological Management

General On arrival

Journey planning • Arrive at night fall

• Arrive mid afternoon

Pre-adaptation • Eastbound: Rise 1 hour earlier

• Westbound: Stay up 1hr later

• not>1hr p.d before departure

• Full adaptation not

recommended for

trips only 1-2d long

Bright light

therapy

• Minimum Core Temp (@ home ±4:30am)

✓ Eastbound: Just after

✓ Westbound: Shortly before

• Blue light (stimulate)

• Amber lenses (block)

• Natural light better

• Avoid screen time in evening

Timing NB in relation to core

temperature

Eastbound:

Westbound:

Eastbound:

Eastbound:

Westbound:

Westbound:

Non-Pharmacological Management

General During flight On arrival

Sleep • Adequate sleep before travel

• More rigid sleeping habits more symptoms

• Schedule flight during sleeping hours at destination

• Least amount of connecting flights

• Set watch to destination time

• Night time at

destination

• Follow time pattern of destination

• Good night`s sleep

• Power naps (20-30min)

• Consistent bed and wake times

• Cool, dark, quiet room

Diet • Timing more important than type of meal

• Avoid alcohol

• Avoid caffeine at night time

• Light energy meals

• Alcohol 2-3x more

potent at flight

altitude

• Hydrate with water

• ? High protein meal improves arousal

• ? High CHO meal improves sleepiness

• Morning caffeine increase alertness

• Hydrate with water

Exercise • Not proven to shift circadian rhythm

• May maintain arousal level

• Change training routine (not coincide with circadian

nadir of 2-4am at departure zone)

• Frequent movement

• Compression socks

• Low to moderate intensity

• Higher risk of injury 1st few days

• Argonne Anti-Jet Lag Diet

• Harvard Anti-Jet Lag Fast

(Limited Evidence)

Simmons E, et al. Jet Lag Modification. Curr Sport Med Report, 2015, 14,2:123-128

Pharmacological Management

General During flight On arrival

Melatonin • Derived from serotonin/tryptophan• Cochrane review in 2002 concluded

exogenous use effective and safe

• Chronobiotic (phase shifter, 0.5mg)

• Chronohypnotic (sleep initiator, 3-10mg)

• Product quality may be a concern

To induce sleep and/or shift the body clock

• Eastbound: 3mg on boarding

• Westbound 0.75mg on rising (day of flight)

To induce sleep and/or shift the body clock

• Eastbound: Low dose (0.75mg) mid afternoon to bedtime advances clock

• Westbound: Low dose (0.75mg) during early morning delays clock

Sleeping tablets • Short acting• Zolpidem + Melatonin increase daytime

somnolence

• No evidence • Recommended in athletes withpersistent insomnia that have tolerated it well before

Stimulants • Most stimulants are banned substances• Consider for team management to assist

with daytime sleepiness (Modafinil)

Melatonin agonists

• Ramelteon and Tasimelteon

• Longer duration of action than Melatonin

• No evidence • No evidence

Melatonergicanti-depressants

• Agomelatine

• Treatment of depressive sx`s associated with jet lag

• No evidence • No evidence

Eastbound:

Westbound:

Eastbound:

Westbound:

Venkatramanujam S, et al. Jet Lag, Circadian Rhythm Sleep Disturbances, and Depression: the Role of Melatonin and its Analogs. Adv Ther, 2010, 27(11):796-813

Conclusion

• Travel fatigue and jet lag poses a big problem for travelling athletes with RF`s including: sleeping habits / chronotype / sex / time zones crossed / flight direction / physical fitness / age / time of destination / previous experience

• Many uncertainties on methods to advance or delay the body clock

• Jet lag calculators:

www.britishairways.com/travel/drsleep/public/en_gb

www.jetlagrooster.com

http://www.britishairways.com/travel/drsleep/public/en_gbhttp://www.jetlagrooster.com/

Christa.JansevanRensburg@up.ac.za

Email: Christa.Jansevanrensburg@up.ac.za

Twitter: @ChristaJVR