Transcript Diet, Exercise & Kids

Research Update
2005 Chiropractic Sports Sciences Symposium
Sports Nutrition
With Strength and Conditioning
Exercise Physiology and
Spine/General Studies with Practical Application
G. Douglas Andersen, DC, DACBSP, CCN
Sugar Utilization During Exercise
• Sucrose (S), fructose (F), maltodextrin (MD), and glucose
(G) are, in part, absorbed by different transport mechanisms
• CHO oxidation during cycling exercise peaks at 1 gr/min for
G1 and MD2
• S+G or F+G peak at 1.25 g/min1
• MD + F (67-33%) reached 1.5 g/ min during exercise2
• A G+S+F mix (50 – 25 – 25%) reached 1.7 g/min during
exercise1
• Endogenous CHO oxidation 25% lower with 3 sugar mix1
1Jentjens,
R.L., Achten, J., Jeukendrup, A.E. High Oxidation Rates from a Mixture of Glucose, Sucrose and Fructose Ingested
During Prolonged Exercise. Med. Sci. Sp. Ex. 2004; 36(5): S19
2Wallis, G.A., Rowlands, D.S., Shaw, C. et al. Oxidation of Comined Ingestion of Maltodextrins and Fructose during Exercise.
Med. Sci. Sp. Ex. 2004; 37(3): 426-432
CHO in Simulated Team Sport Conditions
• No debate on CHO’s ability to improve endurance performance
• Growing evidence that CHO’s help intermit high intensity
exercise as well
• This study showed 6% CHO solution superior to placebo after 415 minute quarters of shuttle drills ranging from running,
sprinting, repeated jumps, to walk/jog, stops/starts, and skill test
• Compared to placebo, CHO drink resulted in faster 20m sprint
time, higher average jump height, better motor skills and
improved mood in the 4th quarter
• This study showed 6% CHO drink preserves both physical and
central nervous system function late in the game
Winnick, J.J., Davis, J.M., Welsh, R.S., et al. Carbohydrate Feedings during Team Sport Exercise Preserve Physical and CNS
Function. Med. Sci. Sp. Ex. 2005; 37(2): 306-315
Carbo Mouthwash
• 9 endurance cyclists (7 M, 2 F) completed 2 set workloads as fast
as possible
• On 8 occasions during the ride, subjects rinsed for 5 seconds with
a 6.4% maltodextrin carb drink (C) or a zero carb placebo (P)
• They were not allowed to swallow either solution
• 7 days later they rode again with the opposite solution
Results
• Power output was greater in 8/9 subjects when they gargled with
CHO drink versus the placebo drink
• Ave power output: C-259 W P-252 W
• Performance times: C 59.57+1.50 min vs. P 61.37+1.56 min
• Are there oral C receptors that stimulate reward or pleasure
centers in the brain?
Carter, J. M., Jeukendrop, A.E., Jones, D.A. The Effect of Carbohydrate Mouth Rinse on 1-h Cycle Time Trail Performance. Med. Sci.
Sp. Ex. 2004; 36(12): 2107-2111
Placebo Sports Drink
• 16 runners randomly ran 5k time trials
• They consumed water or water falsely labeled as a new
ergogenic aid sports drink. They also viewed a video
about how great the product was..
• 12/16 ran faster with the placebo. (21:40 + 2:48 vs. 21:54
+ 3:20) although statistical significance was not achieved
• The final 400 meters were run 2.5 seconds faster with the
placebo
Foster, C., Felker, H., Porcari, J.P, et al The Placebo Effect on Exercise Performance. Med. Sci. Sp. Ex. 2004; 36(5): S171
CHO/Protein Fluid Replacement Drink Improves
Speed & Reaction in Ice Hockey
Methods
• 1 goalie and 4 skaters were NCAA Div 1 hockey players
• Blinded/counter balanced treatment
• Consumed 1 quart during two 90 minute practices
• Placebo and 8% CHO/P drinks were reversed 1 wk later
• Shooting drills, sprints, and reaction times were measured
Results
• Skating speed improved 8% (23 vs. 25 seconds)
• Scoring improved from 3.25 to 3.5 goals
• Goalie skate time was faster (4.34 vs. 4.38 seconds)
• Goalie reaction time was faster (R & L) .126/.126 vs. .138/.146
Olson, B., Seifert, J. The Effects of a Carbohydrate/Protein Dink on Skating Performance in Collegiate Hockey Players. Med. Sci. Sp.
Ex. 2004; 36(5): S13
CHO & Protein drink vs. CHO drink
on time to Fatigue & Muscle Damage
• 15 cyclists rode exercise bike to exhaustion at 70% VO2 max
and repeated ride 12-15 hr later at 85% VO2 max
• They consumed either 7.3% CHO drink or 7.3% CHO drink
with 1.8% whey protein at a rate of ~ 4oz per 15 min
• 14 days later the test was repeated with the other solution
Results
Ride 1
Ride 2
CHO
82 min
31 min
CHO + P
106 min
44 min
% longer CHO +P
29%
40%
• Adding P to CHO beverage improved performance in both
rides regardless of what order the subjects got the CHO +P
drink
CHO/P drink vs. CHO drink Cont…
• Time of exhaustion with CHO drink was 82 min.
• At 82 min., CHO calories ingested were 186; CHO +P calories
ingested were 232
• At 106 min. total caloric intake for CHO + P riders was 325 kcal
• Total calories expended at end of CHO +P ride were an
additional 318 kcal more than the CHO ride - but only 139 more
calories were ingested
• Previous studies have shown CHO +P accelerates glycogen
resynthesis1 and storage2 - Thus, ride one improvement may be
explained via increased resynthesis while the ride two benefit is
likely due to greater storage of glycogen
1Lvy,
et al. J Appl. Physiol. 93: 1337-44, 2002
2Willaims, et al. J Strength Cond. Res. 17:12-19, 2003
CHO/P drink vs. CHO drink
cont… on Muscle Damage
• Creatine phosphokinase (CPK) is a good indicator of muscle
damage
• CPK was measured 30 min prior to the 1st ride to exhaustion
and again 12-15 hrs later
• Pre ride CPK levels were the same in both groups. Post ride
levels averaged 1318 u/L for CHO and 216 u/L for CHO –P
were 83% less
• This indicates 1.8% P added to a 7.3% CHO drink reduced post
exercise muscle damage and increased time to exhaustion (in
both rested and recovering rides) when compared to a 7.3%
CHO only drink.
Saunders, M.J., Kane, M.D., Todd, M.K. Effects of a Carbohydrate-Protein Beverage on Cycling Endurance and Muscle Damage.
Med. Sci. Sp. Ex. 2004; 36(7): 1233-1238
Glycemic Index Meals – Low vs. High
• 8 21– 23 yr old males preformed a treadmill run for 90 minutes at
70% VO2 max
• 8 g/kg/bw CHO for 24 hrs was either low or high GI Index
• Following overnight fast, 70% VO2 max run to exhaustion
• Average time to exhaustion, Low GI – 108 min. Hi GI – 96 min.
Comments
- Results suggest improvement was due to greater fat oxidation
during the run to exhaustion on an empty stomach 24 hrs later
- Pearl: Hi GI carbs for 1st 2-4 hrs post exercise, then low GI foods
for the next 20-22 hours
Stevenson, E.J., Willaims, C., McComb, G., et al. Improved Recovery from Prolonged Exercise Following the Consumption of Low
Glycaemic Index Carbohydrate Meals. Med. Sci. Sp. Ex. 2004; 36(5): S21
Omega 3 Fatty Acids
• 7 men (23-24 years old) participated in 4 treatment conditions
and then were tested with a glucose challenge 15 hours later
1. 3 days of rest
2. 3 days of a brisk 1 hour walk
3. 3 days of rest after 5-6 weeks of 4.5 gr/d of omega 3 fatty
acid supplements
4. 3 days of brisk 1 hour walk after 5-6 weeks of 4.5 gr/d of
omega 3 fatty acid supplements
Omega 3 Fatty Acids Cont…
• Insulin (uU/ml) response to glucose challenge (15 hrs post ex)
Rest
Rest + Sup.
Walk
Walk + Sup
5805
4961
4403
4194
• Exercise reduced insulin levels 24% vs. rest
• Rest and Omega 3’s reduced insulin 14.5% vs. rest
• Exercise and Omega 3’s reduced insulin 15.5% vs. exercise
Ben-Ezra, V., Clark, S.J., Wooten, J.S., et al. The Independent and Combined Effects of n-3 Polyunsaturated Fatty Acids and
Exercise on Insulin Responses. Med. Sci. Sp. Ex. 2004; 36(5): S173
Protein & Strength
• 51 subjects, 18-25 yrs. old (28 M, 23 F) were in a 6 month
strength and conditioning program
• They received either a - 42 gr protein, 24 gr carb, 2 gr fat
drink twice daily or a 70 gr carb drink twice a day for 6
months. The calories, vitamins and minerals were the
same in both drinks
• Training was 3 d/wk weight training and 3 d/wk running
• Diet records done at baseline, 3 and 6 months indicated no
difference in calories between the groups
• Protein intake was 2.2 g/kg/bw in protein group and 1.1
g/kg/bw in carb group
Protein & Strength Cont…
Baseline
Placebo
Bench Press, kg
Hip Sled, kg
Protein
Bench Press, kg
Hip Sled, kg
3M
6M
55.8 +; 7.2
70.0 +; 8.4
156.2 +; 14.9 205.9 +; 18.8
75.2 +; 7.8
231.4 +; 18.8
53.5 +; 5.9
141.0 +; 12.8
80.8 +; 7.1
216.2 +; 12.4
71.8 +; 6.9
194.9 +; 12.8
• Protein improved bench press but not the hip sled
(GDA: Study should be repeated with more subjects)
Vukovich, M.D., Tausz, S.M., Ballard, T.L., et al. Effect of Protein Supplementation During a 6-month Strength and Conditioning
Program on Muscular Strength. Med. Sci. Sp. Ex. 2004; 36(5): S193
Raisins vs. Sports Gels
• 8 trained cyclists did a 45 minute exercise bike ride followed
immediately by a 15 minute performance trail
• 45 minutes before the ride, 1 g/kg/bw of a sports gel or raisins
were consumed
• The experiment was repeated with the opposite CHO source
• Raisins are considered to be a moderate glycemic index (GI)
food; sports gels are high GI index foods
• There was no difference in performance
• Following exercise, free fatty acids were elevated in the raisin
group but not the gel group
• This study was funded by the California Raisin Marketing
Board
Kern, M., Heslin, C.J., Rezende, R.S. Metabolic and Performance Effects of Raisions Versus Sports Gel as Preexercise Feedings in
Cyclists. Med. Sci. Sp. Ex. 2004; 36(5): S174
Ergogenic Aids – TCA Intermediates
• 3 Tricarboxylic-Acid-Cycle intermediates (pyridoxinealpha-ketogluterate, malate and succinate) with low dose
vitamins, minerals, amino acid, and accessory nutrients (LCarnitine, CoQ10, lipoic acid, inosine, TMG, glutathione)
• Cyclists took the supplement or placebo 2x/d for 3 weeks
• Following 1 week break, cyclists took the opposite
treatment for 3 weeks
• Placebo time to exhaustion was longer (but not statistically
significant)
Brown, A.C., MacRae, H.SH., Turner, N.S., Tricarboxylic-Acid-Cycle Intermediates and Cycle Endurance Capacity. Int. J.
Sport Nutr. Ex. Meta. 2004; 14(6): 720-729
Endurox
• Endurox is standardized ciwujia extract (pronounced su-wah-ja)
• Ciwujia comes from a root grown in NE China
• Product claims include “studies that show”
– Up to 43% in fat metabolism
– Up to 33% reduction in lactic acid
– Heart rate during recovery is 20%
• www.endurox.com does not reference the “studies”
Endurox vs. PowerAde vs. Water
• 18 subjects (20-40; 9 male 9 female)
• 45 minute ride at 65% followed by 2 minute sprint increments
to fatigue
• After 15 minutes of rest, a second incremental ride to fatigue
was done
1st bout E 50.8 minutes PA 51.9 minutes W 52.0 minutes
2nd bout differences were non-significant
Bergen, J.L., McDaniel, K.O., Willhoit, K., et al. Effect of Endurox on Exercise Time to Fatigue, Recovery, and Recovery Exercise
Performance. Med. Sci. Sp. Ex. 2004; 36(5): S174
Iron Deficiency in Female Athletes vs. Non Athletes
• 55 High school seniors in sports and 92 non participants were
tested
• 29/55 athletes (53%) and 43/92 general population (47%) were
iron deficient
• Authors state no statistical difference between athletes and non
athletes
• The percent of iron deficient women in studies does vary
• Pearl – low energy, sleepy after workouts, can’t get in shape,
little or no red meat – think iron!
Landahl, G., Börjesson, M., Rödjer, S. Iron Deficiency-More Common among Female Athletes than Non-athletes? Med. Sci. Sp. Ex.
2004; 36(5): S120
High Dose Vitamin E & Triathlon
• 38 athletes got either 800 IU of Vitamin E (d alpha tocopherol)
or placebo for 8 weeks prior to competing in a 3.9 km swim,
180 km bike, and 42 km run
• The hypothesis was with severe exertion, Vitamin E would
attenuate exercise induced increases in inflammation, oxidative
stress and post race immune suppression
• Plasma alpha tocopherol was 75% higher in the Vitamin E
group
• Plasma oxidative stress markers were 181% higher than pre
race baseline after the race in the Vitamin E group but only 97%
higher in the placebo group
• Vitamin E neither helped or harmed performance. To the
authors surprise, high dose E appeared to increase oxidative
insult
Nieman, D.C., Henson, D.A., McAnulty, S.R., et al. Vitamin E and Immunity after the Kona Triathlon World Championship. Med.
Sci. Sp. Ex. 2004; 36(8): 1325-1335
Antioxidant Food
• Athletes underwent two high intensity run to exhaustion (40
min) treadmill tests
• The exercise test were done after 2 weeks of a diet high in
antioxidants (HAD) and (after washout) repeated the test,
following 2 weeks of a low antioxidant diet (LAD)
• Blood tests revealed increased markers of oxidant stress after
the LAD following sub maximal (+38%) exhaustion (+45%)
and 1 hr of recovery (+31%)
Authors Conclusion
• These deficiencies in antioxidant capacity can be resolved
with food alone
• There is no need for supplements if the diet is adequate
Watson, T.A., Callister, R., Taylor, R.D., et al. Antioxidant Restriction and Oxidative Stress in Short-Duration Exhaustive
Exercise. Med. Sci. Sp. Ex. 2005; 37(1): 63-71
Antioxidants & Post Exercise Oxygen Stress
• 18 obese untrained women ages 19-31 were enrolled in a dbl
blind study
• 9 took 400 IU E, 1000 mg C, 90 mcg Se for 14 days prior and
2 days following eccentric tricep exercise, 9 took placebo
• Eccentric exercise increased the biomarkers of protein
oxidation 200% from baseline in the placebo group but only
50% with antioxidants
• This protection was maintained at 2, 6, 24, and 48 hours
following the workout
Goldfarb, A.H., Bloomer, R.J., McKenzie, M.J. Combined Antioxidant Treatment Effects on Blood Oxidative Stress after Eccentric
Exercise. Med. Sci. Sp. Ex. 2005; 37(2): 234-239
Carnitine
• A dipeptide synthesized from lysine and methionine
• 20 mildly overweight college students took 1 gram TID of
carnitine (C) for one month or placebo (P)
• They were further divided into exercise (Ex) and non exercise
groups
• Comparison of C, C + Ex, P + Ex and P, revealed that C did
lower cholesterol, triglycerides and LDL but had no effect on
body fat, endurance, anaerobic threshold or peak VO2
Choi, E.S., Bae, Y.J., Kim, C.K. Effects of Carnitine Intake and Aerobic Exercise on Blood Lipid Levelsand Physical Performance.
Med. Sci. Sp. Ex. 2004; 36(5): S176
CLA
• Conjugated Linoleic Acid (CLA) research has been quite
successful in reducing fat and increasing lean mass in animals
• Human research has been generally unimpressive
• 77 young (average age 25) subjects (37 M, 40 F) took 5 grams of
CLA/d or placebo for 7 weeks
• Both groups followed the same strength program (3d/wk – 12
exercises – 3-4 sets)
CLA Cont…
Lean mass
Fat mass
Results
CLA
Placebo
+1.4 kg
+0.2 kg
-0.8 kg
-0.4 kg
• No differences in leg press, knee extension or bench press in
women
• Males on CLA increased bench press 31 kg vs. 22 kg for placebo
• 17 subjects volunteered to crossover for 7 more weeks
• The CLA had greater loss of fat mass – 0.2 kg vs. +1.5 kg fat gain
• Males who crossed over did not duplicate bench press gains seen
in the initial phase
Pinkoski, C., Chilibeck, P.D., Candow, D.G., et al. Conjugated Linoleic Acid Supplementation During Strength Training. Med. Sci. Sp. Ex.
2004; 36(5): S284
Glutamine & Endurance
• Glutamine is used for the critically ill and immune suppressed to
maintain muscle mass and/or slow muscle loss in these groups
• Glutamine is the most abundant AA in the human muscle
• It regulates protein balance in skeletal muscle (high levels increase
protein synthesis – low levels cause proteolysis)
• Endogenous levels are depressed in cases of overtraining
• Glutamine sales are based on extrapolation of the above
• The limited studies on athletic use have been generally
unimpressive
Glutamine & Endurance Cont…
• 12 male cyclists aged 19 - 31
• Protocol – Wingate test - exercise to exhaustion - wingate test
#2 - 24 hrs rest -wingate test #3
• Following exercise they were divided into 2 groups: CHO +
glutamine (.3 g/kg/bw) or CHO drink for 6 days
• On the 7th day, a wingate test and exercise to exhaustion was
repeated.
• Results – Time to exhaustion increased 3 minutes in glutamine
group after one week use.
Piattoly, T., Welsch, M.A. L-Glutamine Supplementation: Effects on Recovery from Exercise. Med. Sci. Sp. Ex. 2004; 36(5): S127
Rhodiola Rosea & Endurance
• AKA Golden Root
• Grown in the mountains of Europe, Asia, and America
• Claims include CNS stimulation, increased work performance,
increase muscle strength, also anti cancer cardio protective
• Dbl. Blind study compared one acute dose (200 mg 1 hr prior
to exercise) with 30 days of 200 mg doses and retested
Results- time to exhaustion increased 24 seconds 16.8-17.2 min
with a single pre event dose, all other tests - ability to sustain
attention, visual reaction time, speed of limb movement, and
muscular strength were negative. After 30 days, retesting the
results were unchanged.
Conclusion: 4 weeks of 200 mg/d was no different than a single
dose
De Bock, K., Eijinde, B.O., Ramaekers, M., et al. Acute Rhodiola Rosea Intake Can Improve Endurance Exercise Performance. Int.
J. Sport Nutr. Ex. Meta. 2004; 14(3): 298-307
Cordyceps Sinensis & Rhodiola Rosea
• 17 competitive cyclists were tested, randomized and given
either 3 capsules containing 1000 mg CS, 300mg RR, and
800 mg of a blend of pyruvate, Na and K phosphate,
chromium, ribose and adenosine
• No difference in Peak VO2, time to exhaustion, peak power,
or peak heart rate
• Blood lactate, ventilatory threshold and respiratory
compensation were also unaffected in either a positive or
negative way
Earnest, C.P., Wyatt, F., Lucia, A. Effects of a Cordyceps Sensis and Rhodiol Rosea Based Formula on Exercise Performance
in Cyclists. Med. Sci. Sp. Ex. 2004; 36(5): S171
Oral ATP
• 27 males who lift weights completed a dbl. blind trial
• Randomly they received 150 mg ATP, 225 mg ATP, or placebo
• Testing was done at
1. Baseline
2. 7 days later -75 minutes after the first dose
3. Following 14 days of dosing
• No change in total work, average power or peak power output in
Wingate testing
• Authors conclusion “may provide small ergogenic effect on
muscular strength under some treatment conditions” is based on a
1.5 rep bench press increase from baseline in the 1st of 3 sets.
This followed a 1 rep max which declined 2 kg and preceded the
2nd and 3rd sets which were unchanged
Jordan, A.N., Jurca, R., Abraham, E.H., et al. Effects of Oral ATP Supplementation on Anaerobic Power and Muscular Strength. Med.
Sci. Sp. Ex. 2004; 36(6): 983-990
Creatine, Endurance Exercise Followed by
Resistance Exercise
• 14 College age women (age 19-23) took Creatine or placebo
• Creatine 20g/d x 5 then 3g/d x 7 (12 days total)
Baseline Leg Press
Pre Creatine
1 rep max
190 kg
3 sets (reps)
9.4 - 10.0 - 9.3
#reps 80% of 1RM, 2.5 minute rest between sets
Pre Placebo
179 kg
8.9 - 8.4 - 8.6
Then 12 days of creatine or placebo
Creatine, Endurance Exercise Followed by
Resistance Exercise Cont…
An aerobic task (maximum distance in 20 minutes) was
preformed followed by a one rep maximum test in leg press
and then 3 sets
Aerobic task
1 rep max
3 sets (reps)
12d Creatine
3140 + 244 meters
191 kg
10.1 - 9.6 - 9.9
12d Placebo
3420 + 394 meters
181 kg
7.1 - 4.7 - 4.4
Creatine reduced the effect of fatigue on strength loss
Aoki, M.S., Gomes, R.V., Raso, V. Creatine Supplementation Attenuates the Adverse Effect of Endurance
Exercise on Subsequent Resistance Exercise Performance. Med. Sci. Sp. Ex. 2004; 36(5): S334
Acid Buffers
• Energy from continuous high intensity activity causes intra
muscular acidity leading to fatigue
• Hydrogen ions, not lactate ions, cause acidosis
• Improving the capacity to buffer will retard acid accumulation
• Theoretically this will delay fatigue and lengthen time to
exhaustion
• The most common substances are Na bicarbonate, Na citrate, and
Na lactate
• 16 trained runners compared these buffers and a placebo (Na
chloride)
Acid Buffers Cont…
• Na bicarbonate was dosed at 300 mg/kg/bw
• The other substances were dosed at an equal osmotic strength to Na
bicarbonate to control for nausea or GI discomfort
• Na citrate 525 mg/kg/bw, lactate 400 mg/kg/bw, chloride 209 mg/kg/bw
• Subjects ingested 20 to 60 capsules depending on bw over a 90
minute period
• 90 minutes later a performance test was done
• The protocol was repeated every 2-5 days until treadmill runs were
complete (one with each treatment)
• Time to exhaustion: bicarbonate 82.3 seconds, lactate 80.2 seconds,
citrate 78.2 seconds, chloride (placebo) 77.4 seconds
• 12/16 runners best time was with Na bicarbonate
Van Montfoort, M.C.E., Van Dieren, L., Hopkins, W.G., et al. Effects of Ingestion of Bicarbonate, Citrate, Lactate, and Chloride on Sprint
Running. Med. Sci. Sp. Ex. 2004; 36(7): 1239-1243
DHEA
• Dehydroepiandrostevone (DHEA) and DHEA-Sulfate are
cursors to both testosterone and estrogen.
• 15 men (ages 20-45) took 100 mg DHEA or placebo for 1
month. Following a 3 week washout, treatments were
reversed for another month
• No differences were found on stair climbing, treadmill,
pull-ups, or grip strength
• Testosterone was not elevated
• Exercise induced blood glucose was significantly
increased- it was a completely unexpected finding that
needs more research
Deuster, P.A., Sutton, E., Criqui, M., et al. DHEA Effects on Metabolism and Exercise Performance in Men. Med. Sci. Sp.
Ex. 2004; 36(5): S176
Nandrolone Excretion
• Nandrolone (19 nor-testosterone) AKA “Deca” or Deca
Durobolin is statistically the most common positive found by
doping labs
• It has been used for decades and has been banned by the IOC
since 1976
• Positive tests are declared when its metabolite, 19norandrosterone (19-NA) exceeds 2000 pg. ml in the urine
• 32 males consented to be studied; they all denied steroid use
• Within 3 hours of severe musculoskeletal injury urine was
analyzed for 19-NA
• 19-NA levels ranged from 2 pg. ml to 2800 pg.ml
• 6 weeks after injury subjects underwent a second UA
• 19-NA ranged from 0-540 pg.ml
Kohler, R.M., Lambert, M., Hall, K. et al. The Effect of Musculoskeletal Injury on Endogenous Nandrolone Metabolism. Med. Sci. Sp.
Ex. 2004; 36(5): S171
Nandrolone Elimination
• 24 subjects received 50 mg radio-labelled C13-Nandrolone;
12 get a placebo
• Participants then exercised to exhaustion
• The pattern of the radio-labelled steroid showed commonly
measured metabolities are not accurate due to a large
individual variation from exercise induced synthesis
• Along with the previous study it appears both exercise and
injury can cause a wide range of endogenous production
• In some people; markers of exogenous nandrolone (juicing)
may exceed IOC levels without administration
Baume, N., Avois, L., Cauderay, M., et al. C13-Labelled Nandrolone Excretion in Trained Athletes: Effect of Exercise. Med. Sci.
Sp. Ex. 2004; 36(5): S170
Second Day Effect of Exercise in Heat
• Over 2000 cases of exertional heat illness (EHI) from 1979-1997
were retrospectively analyzed from U.S. Marine Corps records
• In addition to heat at the time of the event, analysis yielded
many cases of EHI on days with temperatures well below the
80°F and above, classified as high risk conditions
• Further research reveled that the hotter the previous day was, the
greater the risk of EHI, even with moderate temperatures on the
following day
• An odds ratio was published. For example the risk of EHI on an
85° day is the same as a 75° day if the previous day was 90°
Wallace, R.F., Kriebel, D., Punnett, L., et al. The Effects of Continuous Hot Weather Training on Risk of Exertional Heat Illness. Med.
Sci. Sp. Ex. 2005; 37(1): 84-90
Heat Stress & Football Helmets
•
•
•
•
•
Football players were studied in preseason hot conditions
Sensors were placed on the head
Esophageal probe measured core temp
Heart rate monitors were worn
Intermittent sprints in the heat were preformed on
consecutive days with and without helmets
• Helmets significantly increased thermal load including core
temp and heart rate
• Pearl – in hot conditions remove helmets when not playing
Brothers, R.M., Mitchell, J.B., Smith, M.L. Wearing a Football Helmet Exacerbates Thermal Load During Exercise in
Hyperthermic Conditions. Med. Sci. Sp. Ex. 2004; 36(5): S48
Kids & Dehydration
• 58 12 year olds (34 boys, 24 girls) were monitored during a 4
day summer soccer camp
• Boys had three 2 hour sessions a day; Girls had three 1.5 hour
practices per day
• Fluids were available at all times. Coaches encouraged kids to
drink both during frequent breaks or anytime during practice
• Hydration status was measured by urine specific gravity (USG)
Kids & Dehydration Cont…
Boys (%)
Hydration Status
Minimal DHY
Significant DHY
Serious DHY
Total
Day 2 Day 3 Day 4
15
24
16
44
43
37
25
24
22
84
91
75
Girls (%)
Day 2 Day 3 Day 4
9
18
13
26
37
40
52
18
30
87
73
83
Urine Specific Gravity tests (USG) were done in the AM before practice.
Minimal Dehydration =USG 1.020 – 1.024
Significant Dehydration
1.025 – 1.029
Serious Dehydration
1.030 or greater
Walker, S.M., Casa, D.J., Levresult, M.L., et al. Children Participating in Summer Soccer Camps are Chronically Dehydrated. Med. Sci. Sp.
Ex. 2004; 36(5): S180
Obesity Research
• Fitness reduces the rates of coronary artery disease and
cardiovascular event1
• The longer immigrants live in the US the fatter they get. By 15
years or more they exceed US natives classified as overweight and
are within 3% of obese US natives (19% vs. 22%)2
• Higher consumption of sugar sweetened beverages is associated
with weight gain and type 2 diabetes3
1.Wessel,
T.R., Arant, C.B., Olson, M.B., et al. Relationship of Physical Fitness vs Body Mass Index With Coronary
Artery Disease and Cardiovascular Events in Women. JAMA 2004; 292(10): 1179-1187
2 Goel, M.S., McCarthy, E.P., Phillips, R.S., et al. Obesity Among US Immigrant Subgroups by Duration of Residence.
JAMA 2004; 292(23): 2860 -2867
3Schulze, M.B., Manson, J.E., Ludwig, D.S., et al. Sugar-Sweetened Beverages, Weight Gain, and Incidence of Type 2
Diabetes in Young and Middle-Aged Women. JAMA 2004; 292(8): 927-934
Obesity Research Cont…
• Even with CDC obesity deaths overestimated, at current
rates of weight gain, mathematical demographers expect a
potential lifespan decline within the next 50 years unless the
population can find the discipline to reduce consumption and
increase activity – or – a significant medical breakthrough
occurs1
• The 2005 USDA dietary guidelines for exercise have
changed from the 2000 guide. Rather than attempt to
accumulate 30 min. of activity per day, the 2005
recommendations state “60 min. of moderate to vigorous
exercise on most days while not exceeding calorie
requirements is the amount needed to lose weight.2”
1Olshansky,
S.J., Passaro, D.J., Hershow, R.C., et al. A Potertial Decline in Life Expectancy in the United
States in the 21st Century. N. Engl. J. Med. 2005; 352(11): 1139 –1145
2Kuehn, B.M. Experts Charge New US Dietary Guidelines Pose Daunting Challenges for the Public. JAMA
2005; 293(8): 918 - 921
Diet, Exercise & Kids
• 10 kids ages 10-14 spent 2 weeks in a Pritikin residential program
• Foods were high fiber, very low fat, low cholesterol and
consumed ad libitum
• Aerobic exercise daily
Results
Total Cholesterol
LDL
Triglycerides
CRP
Insulin
Pre
164 mg/dl
124 mg/dl
141 mg/dl
4.15 mg/L
22.6 uU/ml
Two weeks later
117 mg/dl
79 mg/dl
80 mg/dl
1.90 mg/L
15.5 uU/ml
Chen, A., Roberts, C., Barnard, R.J., Effect of a Short-term Diet and Exercise Intervention on Serum Insulin, Lipids, Oxidative Stress,
Inflammation, and Adhesion Molecules in Children. Med. Sci. Sp. Ex. 2004; 36(5): S82
Protein Weight Loss & Bone Mineral Density
• 52 (21 M, 31 F) middle aged (mean 48) overweight (BMI
33.7 + 4.5) subjects
• 4 months - 1700 cal/d F - 1900 cal/d M – ‘Active lifestyle’
• HI PRO
1.6 g/kg ~ 30% P 40% C 30% F
• CHO
0.8 g/kg ~ 15% P 55% C 30% F
Results
Ave Wt loss
Fat loss
BMD*
BMC*
PRO
-19 lbs
-13 lbs
+3.0%
+3.7%
CHO
-16 lbs
-10 lbs
+0.9%
+1.5%
*in lumbar spine
Evans, E.M., Heinrichs, K.L., Layman, D.K. Does Protein Intake During Weight Loss affect Bone Mineral
Content and Density? Med. Sci. Sp. Ex. 2004; 36(5): S96
High Carb, Low Protein Beats
High Protein, Low Carb*
• 164 women average age 37 BMI 32.5 + 4
• 1 year - 1200-1500 cal/d - Group sessions and phone calls to
maintain compliance were preformed regularly
• Questionnaires on food and activity were done throughout the year
• Divided into High PRO
High CHO
P 20
P 13
C 45
C61
• Exercise
High CHO 220 + 100 min/wk
• Wt loss
High CHO 22 lbs
F 35
F26
1437 + 583 cal/d
1305 + 604 cal/d
High PRO 160 + 116 min/wk
High PRO 13.4 lbs
*Authors state no statistical difference in energy intake or activity
Mohr, C.R., Jakicic, J.M., Gallagher, K.I., et al. Effect of Macronutrient Composition on 12-Month Weight Loss in Overweight Women.
Med. Sci. Sp. Ex. 2004; 36(5): S97
Fitness Bodyweight & Disease
• Results of 24 year follow-up of The Nurses Health Study,
116,500 women between 30 and 55 in 1976
• Modest adult weight gain increases risk of reduced lifespan
• Physical inactivity (less than 3.5 hr/wk a.k.a. 30 min/d)
reduces lifespan
• Adiposity predicted higher death rate regardless of activity
• Activity was beneficial at all levels of adiposity but could
only reduce, not reverse, the increased risk of death with
obesity
Hu, F.B., Willett, W.C., Li, T., et al. Adiposity as Compared with Physical Activity in Predicting Mortality among Women. N.
Engl. J. Med. 2004; 351(26): 2695-2703
Parents & Obese Children
• 947 surveys to parents of 2nd, 3rd, and 4th graders in 5 NY
schools
• 127 survey’s were completed
• 79% of overweight parents had overweight kids
• 88% of parents correctly classified their children as normal or
overweight
• Of the 12% who misclassified their kids, 15/16 said their
overweight child was normal weight
• Pearl – It is not normal to be overweight
Keller, B.A., Miner, J.K., Wigglesworth, J.K. The Role of Parents in Factors that Contribute to obesity in Children. Med. Sci. Sp.
Ex. 2004; 36(5): S51
Could the Obesity Problem be Caused by Food?
• 13 subjects (9 M, 4 F) mean age (23) BMI 23.2 were deceived into
thinking they were in a taste and food perception study
• The study began with subjects getting a buffet lunch which
researchers then weighed and analyzed for amount of energy they
self selected. When they finished lunch, any leftovers were again
analyzed
Monday
Wednesday
Friday
Week 1Buffet lunch
Buffet lunch
Buffet lunch
Week2
Group A (100%) Group A (150%) Group A (125%)
Group B (125%) Group B (100%) Group B (150%)
Group C (150%) Group C (125%) Group C (100%)
• Percentages refer to the average amount consumed in the first week
Could the Obesity Problem be Caused by Food?
Cont..
•
•
•
•
•
In week 2 they were divided into 3 groups
The self selected buffet meal was referred to as 100%.
The self selected meals averaged 698 kcal
The 863 kcal were consumed from the 125% plate
The 971 kcal were consumed from the 150% plate
Results
• The amount of food consumed was not associated with hunger
• The amount of food consumed was directly associated with the
amount served
Levitsky, D.A., Youn, T. The More Food Young Adults Are Served, the More They Overeat. J Nutr. 2004; 134: 2546-2549
Single vs. Multiple Sets
• 1 set of 10 reps of 10 different exercises was compared to 3
sets ( same reps, same lifts)
• Energy Expendative (EE) during and following was measured
1 set
3 sets
During
75 kcal
208 kcal
Post Ex*
36 kcal
51 kcal
Total
111 kcal
259 kcal
*kcal in 120 min post exercise. After 2 hours both groups resting
EE returned to baseline.
Henley, M.O., Irving, B.A., Gaesser, G.A. Effect of Singles- and Multiple-Set Resistance Exercise on Postexercise Energy
Expenditure. Med. Sci. Sp. Ex. 2004; 36(5): S277
EPOC, TRIMPS & Intensity
• EPOC – Excess Post-exercise Oxygen consumption
• TRIMPS – The index of training load (calculated from the relative
duration and intensity multiplied by a factor describing blood
lactate vs. relative intensity relation)
• 8 men (28 yrs old + 4) ran an inclined treadmill on 3 occasions
EPOC
TRIMPS
Peak HR
1.21 min at 68% VO2 max 58 ml/kg
39 arb. units 165
2.40 min at 68% VO2 max 115 ml/kg
48 arb. units 177
3.21 min at 79% VO2 max 121 ml/kg
57 arb. units 182
• Intensity increased training load more than duration did
Rusko, H.K., Pulkkinen, A., Martinmaki, K. et al. Influence of Increased Duration or Intensity on Training Load as evaluated by EPOC
and TRIMPS. Med. Sci. Sp. Ex. 2004; 36(5): S144
Low Back Pain in Wrestlers
• This study begins with 3 references to support this statement
“85% of male gymnasts, 80% of weightlifters, 69% of
wrestlers, 58% soccer players, 50% of tennis
players, 30% golfers, and 40-60% of general
population were reported to have low back pain”
Low Back Pain in Wrestlers Cont…
• 53 Collegiate wrestlers got x-rays, MRI’s, and then had trunk
flexor and extensor muscle strength tested at 3 angular
velocities
• Based on imaging, wrestlers were divided into a radiological
abnormality (RA) and non RA (NRA) groups
• 35/53 had RA (66%) 18/53 (34%) had normal studies
• 14/35 in RA group (40%) had LBP 8/18 (44%) in NRA group
had LBP
• There was no correlation between trunk flexor strength and
LBP in either group
• Weak extensors correlated to LBP in the NRA group but not the
RA group
Iwai, K., Nakazto, K., Irie, K., et al. Trunk Muscle Strength and Disability Level of Low Back Pain in Collegiate Wrestlers. Med.
Sci. Sp. Ex. 2004; 36(8): 1296-1300
Low Back Braces
• Many companies advocate low back braces to prevent
injuries in repetitive lifting environments
• 12 subjects (average 50 yrs old) lifted a 25 lb milk crate 4x
per minute for 15 minutes on two occasions – with and
without a back brace. They also did a no load, no brace set.
• 3 sets of fluoroscopic images were obtained – no load, load
without brace, load with brace
• Images were analyzed for joint angles and disc deformation
• Conclusion: Compressive and shear disc deformation was
reduced with back braces in the upright position. The
reduction of forces in flexed postures was insignificant.
Debeliso, M., O'Shea, P., Harris, C., et al. The Effects of a Back-Belt on Lumbar Disc Deformation During Stoop Type Lifting.
Med. Sci. Sp. Ex. 2004; 36(5): S348
Chronic LBP & Brain Atrophy
• 26 chronic low back (LBP) patients were compared to
matched controls
• LBP were subdivided into neuropathic (sciatic nerve damage)
and non-neuropathic groups
• MRI brain scan data, automated analysis techniques voxelbased morphometry and non parametric statistics technique
were employed
Chronic LBP & Brain Atrophy Cont…
•
•
•
•
•
Results
LBP patients shared 5-11% less neocortical gray matter
volume than control
This is equivalent to what is lost in 10-20 yrs of normal
ageing
Each year of chronic pain reduced 1.3 cm3 of gray matter
The gray matter lost occurred in the dorsolateral prefrontal
cortex bilaterally and right thalamus
There were distinct patterns for neuropathic and nonneuropathic LBP patients
Apkarian A.V., Sosa, Y., Sonty, S., et al. Chronic Back Pain is Associated with Decreased Prefrontal and Thalmic Gray Matter
Density. J Neuroscience. 2004; 24(46):10410-10415
Magnets Negative for DOM’s
•
•
•
•
10 males 10 females aged 18 – 32
Dbl blind placebo control
2 sets of 25 reps eccentric elbow flexion to induce soreness
After exercise they were given armbands with magnets or
placebo and were worn 7 days
• Magnets had no effect on reducing pain and swelling, nor
did they prevent strength loss
Mikesky, A.E., Hayden, M.W. Effect of Static Magnetic Therapy on Recovery from Delayed Onset Muscle Soreness
(DOMS). Med. Sci. Sp. Ex. 2004; 36(5): S16
Testosterone Works!
• 60 young men (average age 26, range 18-36) and 60 old men
(average age 66, range 60-75) were involved in a 20 week study
and were randomly assigned to one of five doses (20,50, 125,
300 or 600 mg/wk) of testosterone enanthate.
Results
• In both young and old men, there was a dose dependant
correlation between the amount of steroid and the amount of
muscle growth.
Pearl – More roids = bigger buff….duh
Magliano, L., Woodhouse, L.J., Bhasin, S., et al. Testosterone Dose-Dependently Increases Skeletal Muscle Mass (SMM) in Healthy
Men. Med. Sci. Sp. Ex. 2004; 36(5): S238
American College of Sports Medicine Position Stand
Physical activity and Bone Health
Exercise Rx
Mode:
weight-Bearing endurance activities (tennis; stair climbing;
jogging; at least intermittently during walking), activities that
involve jumping (volleyball, basketball), and resistance exercise
(weight lifting)
Intensity:
moderate to high, in terms of bone-loading forces (60% of 1 rep
max)
Frequency:
weight-bearing endurance activities 3-5 times per week; resistance
exercise 2-3 times per week
Duration:
30-60 min•d-1 of a combination of weight-bearing endurance
activities, activities that involve jumping, and resistance exercise
that targets all major muscle groups
NOTE: Exercise programs for elderly women and men should include not only
weight-bearing endurance and resistance activities aimed at preserving bone
mass, but also activities designed to improve balance and prevent falls
Kohrt, W.M., Bloomfield, S.A., Little, K.D., et al. Physical Activity and Bone Health. Med. Sci. Sp. Ex. 2004; 36(11): 1985 -1996
Asplund, C.A., Brown, D.L. The Running Shoe Prescription. Phys Sportsmed 2005; 33(1): 17-24