New Research in New Research in Cross-Country Skiing Cross-Country Skiing

Physiology & Physiology & Common Training Common Training

MistakesMistakesJulie Downing, PhD, FACSMJulie Downing, PhD, FACSMCentral Oregon Community CollegeCentral Oregon Community College

Health & Human Performance Professor,Health & Human Performance Professor,

Exercise Physiology Lab Director, &Exercise Physiology Lab Director, &

National Chair of ACSM Personal Training National Chair of ACSM Personal Training CommitteeCommittee

COCC Exercise COCC Exercise Physiology LabPhysiology Lab

Cool New Physiology StuffCool New Physiology Stuff

1)1) Upper Body PowerUpper Body Power

2)2) Lactate ThresholdLactate Threshold

3)3) VO2max VO2max

4)4) Jumping (OSU & MSU)Jumping (OSU & MSU)

5)5) Pre-Stretch?Pre-Stretch?

1) Upper Body Power1) Upper Body Power

• > 50 % propulsive force in skate-> 50 % propulsive force in skate-skiing comes from upper bodyskiing comes from upper body

• Highly correlated to xc ski Highly correlated to xc ski performanceperformance

• Shorter, Rundell, Gaskill, Heil, Shorter, Rundell, Gaskill, Heil, Bacharach, Street (SCSU & MSU)Bacharach, Street (SCSU & MSU)

2) Lactate Threshold2) Lactate Threshold• Lactate – Sports bad boy gone Lactate – Sports bad boy gone

good!!good!!• Can be recycled & Can be recycled &

used as fuel. used as fuel. • Heart prefers lactateHeart prefers lactate• Leading researcher – Leading researcher –

George Brooks @ UC George Brooks @ UC

BerkeleyBerkeley

3) VO3) VO22maxmax• Fit Fat Studies done by Fit Fat Studies done by

Epidemiologist Dr. Steven Blair @ Epidemiologist Dr. Steven Blair @ Cooper Institute in Dallas, TX Cooper Institute in Dallas, TX

• Thin Fit = least risk of CVD deathThin Fit = least risk of CVD death• Fat Fit = 2Fat Fit = 2ndnd • Thin Unfit = 3Thin Unfit = 3rdrd

• Fat Unfit = greatest risk of CVD Fat Unfit = greatest risk of CVD deathdeath

3) VO3) VO22max & agemax & age

Main reason seniors are slower is the decrease Main reason seniors are slower is the decrease in VO2max. in VO2max. How?How?

• VO2max = SV x HR x avO2diffVO2max = SV x HR x avO2diff

• Inactive Max HR goes down 10 beats/10 yrsInactive Max HR goes down 10 beats/10 yrs• Active Max HR goes down Active Max HR goes down 5-7 beats/10 yrs5-7 beats/10 yrs• Inactive VO2max decrease = 10%/decade after age 25Inactive VO2max decrease = 10%/decade after age 25• Active VO2max decrease = Active VO2max decrease = 5%/decade after age 255%/decade after age 25

• Also, seniors don’t recover as fast after exerciseAlso, seniors don’t recover as fast after exercise

4) Jump Training4) Jump Training

• Forces calcium into the bones Forces calcium into the bones increasing bone mineral density increasing bone mineral density (OSU falling studies-Snow & (OSU falling studies-Snow & Winters)Winters)

• Vertical Jump Correlation to xc ski Vertical Jump Correlation to xc ski performance (MSU Heil grad performance (MSU Heil grad student 2009)student 2009)

5) To stretch or not to 5) To stretch or not to stretch?stretch?

• Warm-upWarm-up• Pre-stretch?Pre-stretch?

– Depends on dynamic or static Depends on dynamic or static activity?activity?

• ActivityActivity• Cool-downCool-down• Post-stretch – Post-stretch – YES!YES!

Common Training Common Training MistakesMistakes

1) Not following “hard-easy” principle2) Not cooling down effectively3) Not eating right after exercise (high-

glycemic index foods) & eating too much protein

4) Not periodizing training5) Not scheduling complete rest days,

active recovery days, & cross-training days

6) Increasing volume >10%/wk after 20 min goal

7) Focusing too much on cardio & not enough on jumping & upper body power

8) Training in “No Man’s Land”

THANK YOUTHANK YOU