Research Update2005 Chiropractic Sports Sciences Symposium

Sports Nutrition

With Strength and ConditioningExercise 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 4-15 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 measuredResults• 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 CHO CHO + P % longer CHO +PRide 1 82 min 106 min 29%Ride 2 31 min 44 min 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, 20022Willaims, et al. J Strength Cond. Res. 17:12-19, 2003

CHO/P drink vs. CHO drinkcont… 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 3M 6MPlaceboBench Press, kg 55.8 +; 7.2 70.0 +; 8.4 75.2 +; 7.8Hip Sled, kg 156.2 +; 14.9 205.9 +; 18.8 231.4 +; 18.8ProteinBench Press, kg 53.5 +; 5.9 71.8 +; 6.9 80.8 +; 7.1Hip Sled, kg 141.0 +; 12.8 194.9 +; 12.8 216.2 +; 12.4

• 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 (pyridoxine-alpha-ketogluterate, malate and succinate) with low dose vitamins, minerals, amino acid, and accessory nutrients (L-Carnitine, 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…

ResultsCLA Placebo

Lean mass +1.4 kg +0.2 kgFat mass -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 retestedResults- 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 Pre Placebo

1 rep max 190 kg 179 kg3 sets (reps) 9.4 - 10.0 - 9.3 8.9 - 8.4 - 8.6#reps 80% of 1RM, 2.5 minute rest between sets

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

12d Creatine 12d PlaceboAerobic task 3140 + 244 meters 3420 + 394

meters1 rep max 191 kg 181 kg3 sets (reps) 10.1 - 9.6 - 9.9 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, 19-norandrosterone (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 (%) Girls (%)Hydration Status Day 2 Day 3 Day 4 Day 2 Day 3 Day 4

Minimal DHY 15 24 16 9 18 13

Significant DHY 44 43 37 26 37 40

Serious DHY 25 24 22 52 18 30

Total 84 91 75 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 Pre Two weeks laterTotal Cholesterol 164 mg/dl 117 mg/dlLDL 124 mg/dl 79 mg/dlTriglycerides 141 mg/dl 80 mg/dlCRP 4.15 mg/L 1.90 mg/LInsulin 22.6 uU/ml 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 PRO CHOAve Wt loss -19 lbs -16 lbsFat loss -13 lbs -10 lbsBMD* +3.0% +0.9%BMC* +3.7% +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 P 20 C 45 F 35 1437 + 583 cal/d

High CHO P 13 C61 F26 1305 + 604 cal/d

• Exercise High CHO 220 + 100 min/wk High PRO 160 + 116 min/wk

• Wt loss High CHO 22 lbs 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 1 Buffet 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 voxel-based 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 non-

neuropathic 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 RxMode: 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