Losing & Making Weight for Athletes

From Science to Practice

Helen O’Connor PhD APD

Exercise & Sport Science

University of Sydney

Presentation Overview

• Why athletes need to reduce weight/fat

• Challenges for weight and fat loss

• Strategies for weight and fat loss

• Risks of weight/fat loss

• Making weight

• Weight management tool kit

Why athletes reduce weight or fat

• Aesthetic Sports

– ‘Right’ appearance is important

– e.g. Body building; gymnastics

• Endurance Sports

– Carry weight over a distance

– e.g. Distance running; triathlon

Why athletes reduce weight or fat

•Jumping Sports

– Carry weight through space

– High and long jump

•Weight Category Sports

– Competition rule

– Light weight rowing; boxing, martial arts

Note

Most sports consider the additional energy

cost, increased resistance or reduction in

speed or power to weight ratio from excess

body fat when evaluating ideal weight and fat

levels for their sport.

Differences within one Sport

Difference in physique

apparent on casual

observation

Physique and Running

Physique & Swimming

Dawn Frazer 100 mtr Freestyle

Olympian 1956, 1960, 1964

Shane Gould 1972 5 Olympic Medals

Freestyle & IM

Libby Trickett 2009 Olympian

Freestyle & Fly

Getty Images

Morphological Optimisation

Quantified using three kinds of comparisons

• Athlete versus source population

• Competition level gradients

– ‘Best’ versus ‘Rest’ analysis

• Comparison across time

Athlete vs Source Population

‘Best’ vs “Rest’ Analysis

59

60

61

62

63

64

65

66

67

68

I S C

Competition Level

We

igh

t (K

g)

International and Australian 5000-1000 m runners across competitive levels

(unpublished data): I: International; S: State: C: Club

Mechanisms for Optimisation

Selection

•Height, lengths

•High Jump

•Height & high centre of gravity

Adaptation Mass, fat & lean

Mass energy expenditure

Body fat power: weight

Improved heat exchange

Mechanisms for Optimisation

Heat Exchange

Physique & Performance

Olympic Games 1968

Richard ‘Dick’ Fosbury

The Fosbury Flop Technique •curved run-up allows more speed to

do a more powerful jump

•the centre of gravity is underneath,

an indisputable mechanical

advantage.

10 cm Increase in height of male

competitors over 2 Olympiads Uwe Hohn 1984 Games

Does weight/fat loss

improve performance?

• Limited research data (p values)

• Hard to measure effect small weight/fat changes

• Olds et al 1993 (mathematical modeling)

4000 m Pursuit Cycling

– 2 kg body fat 1.5 s (20 m)

40 km Time Trial

– 2 kg body fat 15 s (180 m)

Weight & Fat Loss

• Challenges

• Strategies

Challenges for

Weight or Fat Loss

Challenges for weight or fat loss

• Genetic predisposition

• Gender & pubertal influences

• Media pressures

• Training & appetite

• Tapering

• Under-reporting or energy

deficient?

Heritability of Adiposity

Author Year n Age Heritability

Feinleibet et al 1977 514 Adult 0.64

Fabsitz et al 1980 1028 Adult 0.80

Stunkard et al 1986 4071 Adult 0.77

Bouchard et al 1987 156 Adult 0.10

Bodrtha et al 1990 259 11 0.54

Korkeila et al 1991 7245 Adult 0.73M; 0.68F

Maes 1992 105 Adult 0.89M; 0.49MF

Allison et al 1994 496 Adult 0.93

Bowen et al 1997 105 10-14 0.90

Reviewed Keller et al 2003

Gender & Pubertal Development

Media Influences

'Size zero' causes racket

Daniela Hantuchova

"In tennis, as in all women's sport, there is a lot of

talk about women's bodies”.

“People are looking at your body the whole time.

A male athlete is allowed to be overweight, that's

no big deal”.

“But for a female athlete to be overweight, now

that's seen as the worst thing in the world”.

Detraining and Fat Gain

Elite female swimmers

• Rest period (2 months)

• 4.8 kg body weight gain

• Energy equivalent = 170 MJ

• 170 MJ = training EE

• Energy intake not spontaneously reduced

Almeras et al 1997. `

McConell et al 1993 Distance runners

4 week progressive taper, fat increased 10.4-11.8%

Other Issues with Taper

• Habitual Energy Expenditure

– Usually reduced

• Time

– More time

– Eating when stressed or bored

• Eating away from home

– Meals may be more energy dense

– Buffet food service, free, new, interesting foods – ‘try it’

• Incorrect competition advice

– ‘Fuel up for competition’

Strategies for Weight or Fat Loss

• Macronutrient

manipulation

• Energy Density

• Food variety

• Glycaemic Index

• Role of dairy

• Gut microbiota

• Adjunctive agents

Why Low CHO Diets?

• Currently popular

• Athletes/coaches – Frustrated with weight/fat loss

– Like something ‘newer’

• Claims for substantial weight loss – Longer term safety?

– Effectiveness?

– Performance?

Comparison of

Atkins, Zone, Ornish & LEARN

-6

-5

-4

-3

-2

-1

0

0 2 6 12

Time (months)

Mean W

eig

ht C

hange (

Kg)

Zone

LEARN

Ornish

Atkins

Gardner et al 2007

25

High Protein Diets & Weight Loss

Wycherley et al 2012

Diogenes Weight Maintenance

LP-HGI &

Control

Most Weight

Regain

HP or LGI

alone

moderate

benefit

0.93 kg less

gain in HP &

0.95 kg less

in low GI

HP-LGI

best

Larsen et al 2010

How Much Protein Do We Need?

• Evidence of a ‘set point’ requirement for protein

• Different requirement across species

• Eating continues until protein requirement is reached

• Known as ‘Protein Leverage Hypothesis’

Case Example

• Energy Needs 10,700 kJ/day

• Estimated protein requirement (1500 kJ/day)

• Remainder from carbs and fat (9,200 kJ/day)

• You keep eating until protein intake is satisfied

Excess CHO/Fat

consumed to meet

Protein target

Eaten quota of CHO + Fat but still

eating to get Protein requirement

Eaten quota of kJ but still short of protein

Simpson & Raubenheimer 2005

Energy Density Vs Fat

0

2

4

6

8

10

12

14E

ne

rgy

In

tak

e (

MJ

)/d

Calorimeter VED Free-Living VED Free-Living CED

Impact of dietary fat content on spontaneous food intake under different

experimental conditions (ED = energy density). Stubbs et al 1995

Food Variety

• Diets matched ED & macronutrient content

• Containing either 5, 10 or 15 items

• 6 day duration

• Energy intake increased (400 kcal/d) with variety

• Fad Diets typically have low food variety

• Monotony may be a short term strategy

Stubbs, 2001

Low GI Meals are More Satiating

0

1

2

3

4

5

6

7

Low GI Medium GI High GI

En

erg

y i

nta

ke f

or

rem

ain

der

of

the

day (

MJ)

P<0.05

Voluntary food intake of 12 obese teenage boys following test breakfast & lunch of varying GI

Ludwig et al 1999

Dairy Intake &

Weight & Fat Loss

0

1

2

3

4

5

6

7

Weight Body fat Lean mass

Lo

ss (

kg

)

Control

Yoghurt

Zemel et al 2005

* P < 0.005

* P < 0.01

* P < 0.05

38 obese adults,

500 kcal deficit

12 weeks

Control diet

0-1 dairy &

400-500 mg

ca2+/d.

Yoghurt diet

3 x 180 g

serves RF

yoghurt & 500-

1100mg ca2+/d

Dairy Calcium & Weight: Systematic review

Abargouei et al 2012

Dairy & Adiposity Mechanisms

Dietary Calcium and/or Dairy Products

Available Energy Energy Utilisation

Increased Satiety

Ca2+- Fatty Acid Soaps

Lipolysis

Lipid Oxidation

Energy Expenditure - TEF

Adapted from Teegarden 2005

Is Excess Body Fat

Just a BUG in the GUT?

Slides compliments of A/Prof Gareth Denyer

http://www.youtube.com/watch?feature=endscreen&NR=1&v=pB5AFW7X5F8

Gut Microbiota & Obesity

Adjunctive Agents

• Dietary supplements

– L-Carnitine

– Chromium picolinate

– Hydroy-methyl-butarate (HMB)

– Conjugated linoleic acid (CLA)

– Herbal supplements

• Pharmacotherapy

– Not permitted

– Not recommended due to side effects

– Ethically appropriate (designed for the obese)

Risks of Weight or Fat Loss

• Endocrine disturbance

• Bone loss

• Weight cycling

• Reduced lean mass

• Illness and immunity

• Disordered eating

• Decreased performance

– ‘the runners trap’

Female Athlete Triad Amenorrhoea

Osteopaenia

Low body

fat or weight

Inadequate energy

Inadequate protein, fat

& micronutrients

High fibre

Heavy training

Body Temperature

Hormone pulsatility Disordered

Eating

Lisa

Corrigan

1500 m

Suzie

Rhydderch

1500 m

Energy Deficiency

Energy Deficiency

(decreased energy availability)

• Inadequate available energy

• < 125 (30 kcal)/kg FFM/d

• Amenorrhoea

• Bone mineral loss

• Misclassified as under-reporters

Energy Deficiency

Periodise Physique

“I need to eat

a lot less to be

lean”

Energy for body functions

Energy

Intake

Energy Burnt Training

- = Regular

Menstrual Cycle

IOC healthy Body Image U-Tube

41

Anezka Ruzucka

Gymnastics, Ukraine

Aiko & Tochi Nakata

Figure Skating Japan

Jessie-lee Nelson

Wrestling USA

Akeyo Abasi

Athletics Kenya

http://www.olympic.org/hbi

Satisfying

your hunger

for GOLD

requires

satisfying

your body’s

need for fuel

‘Making Weight’ Issues

• Weight often lost rapidly prior to competition – Fluid loss or restriction (sauna, rubber suits)

– Food restriction, fasting

– Diuretics, laxatives, vomiting

• Intention is to ensure ‘level playing field’ – Larger athletes still aim to make a lower weight

– Sports vary in the number of categories available

• Competitive success – Defeat opponent rather than personal best

– Use strategies to optimise weight regain

– Negative impact varies depending on sport & weight loss

methods used (> energy + fluid restriction)

http://www.youtube.com/watch?v=x1Plo_5HS

Vw&feature=relmfu

‘Making Weight’ Strategies

• Dehydration – Banned by NCAA for wrestlers

– Aim for no more than 2% body mass

• Diet – Rapid weight loss

• Greater loss of lean mass

• Greater loss in performance

– Adequate carbohydrate to maintain performance

– Protein requirement with energy restriction (~1.2 g/kg)

– Low residue diet

Making Weight

Recovery Strategies

• Electrolytes

– Sodium at least 50 mM

• Diet

– High carbohydrate (replace glycogen stores)

– High GI carbohydrates

Note

The need for rapid weight loss can be minimised by developing a plan for the competition

season which gradually reduces weight within easy reach of the desired level.

In the ‘off season’, athletes should aim to prevent excessive weight rebound.

MSSE Position Stand for Weight Loss in Wrestling:

http://www.ms-se.com/pt/pt-core/template-journal/msse/media/0696b.pdf

Weight Management Tool Kit • Anthropometry –ISAK Training

• Food & Activity History

– Check for lounge Lizards

– Food diary (is it plausible ?)

– Food triggers, psychological issues (body image)

• ‘Test diet’ (prescriptive) + diary

• Incorporate…

– Periodised program

– Meals vs snacks (sit and eat at table)

– Low fat, right CHO, adequate protein & dairy

– Low GI, high fibre, for hungry athletes

– Short term restriction in variety to prove efficacy

– Hunger, satiety and CBT approach (VAS)

– Energy levels and vitality (VAS)

Low Energy Availability

Dietary intake (I) and exercise energy expenditure (E) were controlled to achieve

a balanced (B = 45 kcal/kg FFM/day) and deprived (D 10 kcal/kg FFM/day)

energy availability (A = I-E) treatments. D was achieved by diet restriction in

sedentary (S) women and by exercise in active (X) women

(a) Luteinising hormone (LH) pulse frequency in sedentary (S) and exercising (X)

women with the same energy availability. (b) Reduction in LH pulse frequency

caused by low energy availability in (S) and (X) women P < 0.01 Loucks et al 1998

Low Energy Availability

Women were assigned to contrasting EA 45 and 10, 45 and 20 and 45 and 30 kcal/kg.

All participants performed 15 kcal/kg FFM/day of exercise at 70% VO2 max under

supervision while energy intake was controlled to achieve the intended EA treatments

Incremental effects of low EA on LH pulse amplitude and frequency. Effects are expressed

relative to values at 45 kcal/kg FFM/day. As EA declines from a balance at approximately

45 kcal/kg FFM/day effects begin at a threshold at around 30 kcal/kg FFM/day and become

more extreme as EA is further reduced below 20 kcal/kg FFM/day Loucks et al 1998