petrofsky1-vol5no1 3/8/05 4:05 pm page 124 aerobic ... · combined diet and low-impact aerobic...

Combined Diet and Low-ImpactAerobic Exercise Program: Impacton Weight, Girth, and MuscularStrength, Part 1 Jerrold S. Petrofsky, PhD, JDAmy Morris, BSJulie Bonacci, BSRachel Jorritsma, BSAshley Hanson

Department of Physical Therapy, Azusa Pacific University, Azusa, California Department of Physical Therapy, Loma Linda University, Loma Linda, California

Vol. 5, No. 1, 2005 • The Journal of Applied Research124

exercise program. Control subjects, whodid not engage in the exercise program,showed no significant difference inthese repeat measurements, verifyingthat the loss demonstrated in the activegroup was due to the diet and notexaminer error. Muscle strengthincreases were statistically significant,especially in the abdominal, hamstring,and quadriceps muscles. Blood pressureand heart rate were reduced after the10-day diet and exercise program.Weight loss, for the active (diet andexercise) group, averaged 2.4 ± 1.4 kg.Thus, even a 10-day diet and exerciseprogram can result in significant lossesin girth, increases in strength, and anincrease in cardiovascular fitness.

INTRODUCTIONObesity is an ever-increasing problem inthe United States.1,2 The increase inobesity is highly correlated with both anincrease in cardiovascular disease andthe incidence of diabetes.3 Body fat isnormally regulated through two hor-mones, leptin, and adipoleptin.4 Thesehormones circulate in the blood andregulate appetite and the intermediary

KEY WO R D S : e x e r c i s e, d i e t , w e i g h tl o s s, a e r o b i c s.

ABSTRACTFifty-six subjects were studied in a singleblinded randomized study to assess theimpact of a 10-day weight-loss programwith low-impact aerobics on weight,girth, and muscular strength. Exerciseswere performed for appropriately 60minutes a day, and upper and lowerbody girth, strength changes of thequadriceps, hamstrings, and gluteus max-imus muscles were measured. The sub-jects were broken into 2 unequal groups.One group of 25 subjects did not engagein any exercise or diet programs butwere used for reliability of test measure-ments made at the beginning and end ofthe 10-day period. The second group,the active group (n = 33), exercised 1hour a day in an exercise program fol-lowing video tapes and maintained a1200 calorie per day diet for a period of10 days. The results of the experimentsshowed significant losses in girth, espe-cially around the waist and gluteal areas,which is associated with this diet and

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metabolism of the cells.5 When body fatis high due to either diet or an increasein adiposity, leptin is released into theblood. This normally would reducehunger and increase burning of lipids.The trigger between carbohydrate andlipid metabolism is a nuclear transmit-ter, PPAR alpha and gamma. PPARgamma activates at least 35 genes in thecell to change metabolism betweenlipids and carbohydrates.6,7 When PPARis activated, body metabolism is loweredand enzymes are produced to metabo-lize carbohydrates as a fuel.1 High car-bohydrate and low lipid diets, therefore,through their effect on leptin, promotecarbohydrate metabolism, lower metab-olism in general, and increase hungerthroughout the day.8,9 It is believed thata defect in the leptin receptor causesobesity.10 Thus in people who have adefect in the leptin receptor, the body iscontinually fooled into believing thatthere is little fat storage in the body andhunger is high, satiety low, and carbohy-drate metabolism proceeds at a highrate to produce additional fat.10 Eatinghigh lipid diets therefore, increases ther-mogenesis causing more calories to beburned during the day.4 Diets such asthe Atkins diet promote low glucose andare high fat diets.

The effect of diet and exercisetogether can increase oxidation of lipids,reduce body weight, reduce LDL choles-terol in the blood, fasting glucose, andlower resting blood pressure.1,2,7,8,11,12

While low lipid diets reduce basil metab-olism in the body and activate glucoseuse, diet and exercise together will fur-ther increase basil metabolism causingthe body to burn more calories perhour.1,13 However, the exercise must beconducted for more than 30 minutes.Individuals with a higher aerobic capaci-ty are able to have a larger thermogenicresponse than people with lower aerobiccapacities.14 This increased thermogene-sis can last 12 hours or more.15

Therefore, those who exercise and dietat the same time can benefit greatlyfrom the diet.14,16-18

In general, then, an aerobic exerciseand diet program seem to work welltogether. Diet and exercise then havepositive benefits in terms of reducingblood pressure, heart rate, toning thecardiovascular system, reducing fastingglucose and blood lipids, and decreasingLDL particle size, which can lead to lessplaque deposits in the arteries.19-21 Thus,the answer seems to be simple, exerciseand diet together are beneficial.

While no one disputes the advan-tage of exercise for fitness and weightreduction, diet has been the subject ofcontroversy. Diets such as the Atkinsdiet encourage high fat and high saltfood.22 Such a diet, without exercise,goes against conventional advice andcan have serious consequences, since thebreakdown of fat liberates acid radicals,which cause ketoacidosis.22 Such dietscan also lead to stroke by increasingblood coagulation plasma levels of coag-ulation factor VII, a substance releasedfrom the cell that causes the adherenceof blood clots in blood vessels.23 To com-bat these dangers, conventional pro-grams recommend low fat diets, andexercise.24 However, this is not to saythat the Atkins diet is totally wrong anddiets should be high in glucose and highprotein. This can also have severe conse-quences. As discussed above, one of theconsequences is that high carbohydratediets play a role in weight gain, and anincrease hunger.9,25 But not all carbohy-drates are bad, complex carbohydratesdo not cause diabetes. Therefore in aweight loss regime, simple carbohydratesare to be kept low (low glycemic index),which will result in an increase insatiety.26 The increased satiety afterfoods with a low glycemic index can lastfor as much as 4 hours after a meal.27

While the glycemic index may not applyto older individuals, in terms of increas-

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ing satiety, it does seem to increase sati-ety in younger individuals, includingpreadolescent children.9,28 With a longbout of exercise, perceived exertion wasalso less when individuals are on a dietwith a low glycemic index.2 9 The rapidchange in hormones and metabolism afteringestion of high glycemic foods due torapid gastrointestinal absorption seems tobe the villain in reducing satiety.3 0

In conclusion, a proper diet shouldhave a reduced, but not absent, glycemicindex. The diet should be balanced witha mixture of carbohydrates, lipids, andproteins. In the studies cited above, it isapparent that changes in glycemic indexfrom day-to-day can have an adverseeffect on cellular metabolism and sati-ety. Since fats produce water whenburned and carbohydrates use water,modifying the glycemic index from day-to-day would also have effects on waterretention. Thus an effective diet wouldmaintain a constant, but low glycemicindex with suitable exchanges to allowindividuals to adjust their diet to avoidboredom.

But, as cited above, the exercise pro-gram is also essential in reducing girth,toning muscle, and aiding in the weightreduction process. The exercise programshould involve a good range of motion,

combine both weight and endurancetraining, and increase metabolism to ahigh enough level to increase thermoge-nesis during the diet and enhance weightloss.

In the present investigation, we usedan exercise program that combinedweight and endurance training togetheron an exercise video coupled with a ten-day diet. The diet itself is describedunder methods and involved a constantbut low glycemic index and reducedcalories with exchanges in the diet toallow individuals enough flexibility toavert becoming bored with the diet. Inaddition, low impact aerobics were usedinvolving dynamic exercise while placingthe feet in plastic discs referred to asGliding to allow people to exercise rap-idly and easily on a carpet or woodenfloor and keep impact to a minimum.

The hypothesis to be tested then iswill a constant and low glycemic indexdiet with an hour a day of dynamic exer-cise result in good compliance, loss ingirth, toning of muscle and weight loss.

SUBJECTSThere were 2 groups of subjects in thisstudy. One group of subjects acted ascontrols (n = 25), while the secondgroup formed the active (experimental)group (n = 33). Muscle strength andmuscle girth, before and after 10 days,was measured twice in the controlgroup. The active group, on the otherhand, participated in the diet and exer-cise program for a period of 10 days. Theaverage age, height, and weight of bothgroups of subjects is given in Table 1.Twenty-two control subjects finished thestudy, as did thirty of the subjects on thediet. The subjects that dropped from thediet, dropped due to scheduling andmedical issues unrelated to the study. Allexperimental procedures were approvedby the Human Review Committee atAzusa Pacific University and all subjectssigned a statement of informed consent.


Figure 1. A subject is performing Gliding exer-cises involving hip adduction.



METHODSMeasurement of StrengthIsometric strength of the gluteus max-imus muscle was measured in the supineposition. The exact position is that whichoptimized isolation of each muscle asshown by Kendall.31 A cotton strap wasplaced around the leg and loopedaround an isometric strain gage trans-ducer. The strain gage was linear in therange of 0 to 200 kg of force. The outputof the transducer was amplified by astrain gage conditioner amplifier with again of 1000. The display, a Westin 1971panel meter, was calibrated in force inkilograms. A sample and hold circuit wasused in the strain gage amplifier suchthat subjects could observe their maxi-mum effort and the display held themaximum reading for each force meas-urement.

Girth MeasurementsGirth was measured with a model 67020measuring tape produced by Vital Signs(Country Technology, Gays Mills, Wis).The tape applied 4 g of tension such thata uniform pressure was applied aroundthe body for measurements. Girth wasmeasured at the wrist, at the forearm, 3inches below the olecranon process,around the chest at the level of the thirdthoracic vertebrae, at the umbilicus, atone and two inches above the umbilicus,at one and two inches below the umbili-cus, at the mid-thigh, at the ankle, at theischial crest, at the hip joints, and at two,four, and six inches below the iliac crest.

Finally, at the hip joints a tape wasplaced around the gluteus muscles paral-lel to the floor and the difference in thegirth was recorded when 1.3 kg wasapplied to the tape. In this manner firm-ness of the gluteus muscles could beassessed.

Blood PressureBlood pressure was measured by auscul-tation of the left arm. The systolic bloodpressure was determined as the firstsound as the pressure cuff was releasedfrom 200 mmHg at 3 mmHg per secondas per American Heart Association stan-dards. The diastolic pressure was thechange in sound form sharp to muffle.

Heart RateHeart rate was determined by countingthe radial pulse over a 15-second periodand multiplying by 4.

Video ExerciseThree videotapes were used in the exer-cise program. Savvier LP provided all 3tapes. The first, called the Fat BurningCardio video, involved low impact exer-cise and Gliding disks. The aerobic por-tion of the workout without the Glidingdisks was low-impact aerobics to musicwith a moderator, who directed theexercise. In this manner, exercise wasdone in a regimented manner so that itsimulated working out in a gym and

Figure 2. A subject is performing Gliding exer-cise for knee flexion and extension with theback supine on the floor.

Figure 3. A subject is performing Gliding exer-cise for knee flexion and extension with theback lifted during the exercise to increasethe work rate.



variability in exercise intensity andworkout from day to day was eliminat-ed. The Gliding portion of the videoinvolved placing the feet on plastic disksto aid in reducing the friction during thesliding movement of the legs in theabduction, adduction, and flexion exten-sion directions. The tape lasted approxi-mately 30 minutes. In addition to thisvideo, 2 other videos were used, theTotal Body Sculpturing video, and theUltimate Buns and Legs video. The TotalBody Sculpting video was 55 minutes inlength and involved a pure, heavydynamic workout. The other two videos,the Fat Burning Cardio and UltimateBuns and Legs videos, are 30 minuteseach. During the study, at days 2, 4, and9 the Total Body Sculpture video wasused and on days 1, 3, 5, and 8, subjectsused both the Fat Burning Cardio andUltimate Buns and Legs videos. Day 7was a rest day and no exercise was per-formed; on day 6 only the Fat BurningCardio video was used.

Assessment of ComplianceCompliance with the program wasassessed in 2 ways. A six-point scale wasused to assess exercise compliance. Thescale used is as follows: 0, did not exer-

cise at all; 1 = exer-cised 1 day of the 6required; 2 = exer-cised 2 days of the 6required; 3 = exer-cised 3 days of the 6

required; 4 = exercised 4 days of the 6required; 5 = exercised 5 days of the 6required; and 6 = exercised all 6 days.

There was also a diet compliancescale as follows: 0 = deviated from thediet completely all days; 1 = deviatedfrom the diet 9 days; 2 = deviated fromthe diet 8 days; 3 = deviated from thediet 7 days; 4 = deviated from the diet 6days; 5 = deviated from the diet 5 days; 6= deviated from the diet 4 days; 7 =deviated from the diet 3 days; 8 = devi-ated from the diet 2 days; 9 = deviatedfrom the diet 1 day; and 10 = did notdeviate. For the diet compliance scale,subjects were asked to complete the logsheets on a daily basis for complianceand log any foods they ate that were noton the diet and the date.

DietThe diet used in this study had a mixedcomposition of carbohydrates, protein,and fats. The caloric composition of thediet and the number of calories for the10 days is shown in Table 2. The goal ofthe diet was to restrict energy by 500 to1000 kcals per day for most people andto produce a steady, maintainable weightloss. Glycemic index was kept low toincrease satiety after the meal and

Table 1. General Characteristics of Subjects*

Age (years) Height (cm) Weight 1 Weight 2 Change wtActive Group 39.5 164.7 81.6 79.2 -2.4SD 10.3 9.4 16.7 16.2 1.4Control Group 25.6 164.6 66.7 66.7 0.0SD 2.1 9.3 10.3 10.7 0.6

*Weight is measured in kg.

Table 2. General Composition of Diet

Protein Carbohydrate Composition Composition Lipid Composition31% 44% 25%



thereby reduce cravings. There is a highfiber provision in the diet averaging 28grams per day to reduce the risk of car-diovascular disease and cancer. Sodiumhowever, was left low to avoid watergain and was kept at less than 2400 mLper day. The diet consisted of 3 mealsand 2 snacks per day to, again, avoidhunger between meals. The diet itselfincluded a variety of fruits, vegetables,and whole grains, unsaturated fats, andlean protein to maintain good healthand optimum energy. Participants wereencouraged to drink 8 to 10 glasses ofwater per day at a minimum. This dietthen complies with guidelines for propernutrition during dieting as referred to inan article by the American DiabetesAssociation.32 Fruit and vegetableexchanges are shown on Table 3, and thefruit exchanges allotted on the diet andtheir amounts are shown on Table 4. Thedaily diet plan is shown in Table 5.

ProceduresSubjects were medically screened forcardiovascular and neurological disor-ders. Girth was measured at the umbili-cus, above and below the umbilicus, atthe ischial tuberosity, at the top, middleand bottom of the thigh, and on the armand the wrist. Blood pressure and heartrate were measured on all subjects aswell. Muscle strength was measured inthe quadriceps, hamstring, and gluteusmaximus muscles. All the above meas-urements were repeated before and onthe tenth day after initiation of the exer-cise and diet program. For control sub-jects, data was repeated before and afterthe 10-day period absent a diet andexercise program.

RESULTSThe results of the experiments areshown in Tables 6 to 11. As seen in Table6, compliance was calculated, as

Table 3. Vegetable Exchanges on Diet*

Artichoke (1/2 medium) Lettuce (dark preferred)Asparagus MushroomsBeans (green, wax, Italian) OkraBean sprouts Onions & green onionsBeets Pea pods (snow peas)Broccoli Peppers (green, red and yellow)Brussels sprouts RadishesCabbage & Chinese cabbage RutabagaCarrots Salad greensCauliflower Sauerkraut (low sodium)Celery SpinachCucumber Summer squash (yellow or zucchini)Eggplant Tomato (one medium or 5 cherry)Endive Tomato/vegetable (low sodium)Escarole TurnipsGreens (collard, mustard, turnip) Water chestnutsHot peppers (Jalapenos)KaleKohlrabiLeeks

*1/2 cup of cooked or 1 cup of raw vegetables can be substituted from the list.



described under methods, for both theexercise and the diet. For the exercise,the average compliance is as shown inTable 6 was 84%. For the 30 subjects inthe study, the average diet compliancewas 83%. Thus by averaging the twotogether the total compliance was 83%.

The change in strength of thequadriceps, hamstrings, and gluteus max-imus muscles is shown in Table 7 as themean of all the subjects’ ± the standarddeviation. Significance is also shown atthe bottom of the table as derived froma related t test. The strength of thequadriceps, hamstrings, and gluteus max-imus muscles was 48 ± 19.6 kg, 31.6 ±10.4 kg, and 37.7 ± 10.7 kg, respectively.As shown in this table, the averagechange in strength of the subjects for thequadriceps, hamstrings, and gluteus max-imus for of the 10-day period was 16 ±19.6 kg, 14.1 ± 12.63 kg, and 16.73 ± 21.7kg for the 3 muscles respectively. All dif-ferences were significant. The controlsubjects showed no significant differencein strength over the test period (P >0.05).

Girth measurements showed signifi-cant losses in key areas of the body. Asshown in Table 8, measurements of wristcircumference, forearm circumference,and upper arm circumference, onlyshowed significant changes for the upperarm and forearm. The wrist, as might beexpected, showed no significant differ-ence in these studies. For the controlgroup, there was no significant differ-ence in the pre- and post-test data (P > 0.05).

The most significant changes in girthwere seen in the lower part of the body.In Table 9, the changes in girth are seenfor the umbilicus, above and below theumbilicus, the gluteal area, and leg area.

The greatest changes in girth wereseen at 1/2 inch above the umbilicus. Forthe group, for example, the initial girthwas 95.9 ± 15.9 cm. After the diet andexercise program, the average subject

Table 4. Fruit Exchanges on Diet*

Fresh, Frozen, and Unsweetened Canned Fruit Apples (raw, 2 in. across) 1Applesauce (unsweetened) 1/2 cupApricots (canned) (4 halves) 1/2 cup Banana (9 in. long) 1/2Blackberries (raw) 3/4 cupBlueberries (raw) 3/4 cup Cantaloupe (5 in. across) 1/3Cantaloupe (cubes) 1 cupCherries (large, raw) 12 wholeCherries (canned) 1/2 cupFigs (raw, 2 in. across) 2Fruit cocktail (canned) 1/2 cupGrapefruit (medium) 1/2 Grapefruit (segments) 3/4 cupGrapes (small) 15 Honeydew melon (medium) 1/8Honeydew melon (cubes) 1 cupKiwi (large) 1Mandarin oranges 3/4 cupMango (small) 1/2Nectarines (2 1/2 in. across) 1Orange (2 1/2 in. across) 1Papaya 1 cup Peach (2 3/4 in. across) 1Peaches (canned) (2 halves) 1 cupPear (1/2 large) 1 smallPears (canned) (2 halves) 1/2 cupPersimmon (medium, native) 2Pineapple (raw) 3/4 cup Pineapple (canned) 3/4 cupPlum (raw, 2 in. across) 2Pomegranate 1/2 Raspberries (raw) 1 cup Strawberries (raw, whole) 1 1/4 cups Tangerine (2 1/2 in. across) 2Watermelon (cubes) 1 1/4 cups Dried FruitApples 4 ringsApricots 7 halvesDates (medium) 2 1/2 Figs 1 1/2 Prunes (medium) 3Raisins 2 tbs Fruit Juice Apple juice/cider 1/2 cupCranberry juice cocktail 1/3 cup Grapefruit juice 1/2 cupGrape juice 1/3 cupOrange juice 1/2 cup Pineapple juice 1/2 cupPrune juice 1/3 cup * Servings of fruit may be substituted for anoth-er. Note: All canned fruit must be canned injuice and not sugar syrup.



Table 5. Diet Plan for Typical 3-Day Period

DAY 1Breakfast Egg ScrambleSpray non-stick pan lightly with non-stick sprayand cook onions, bell pepper, and mushroomsfor 2 minutes. Add egg whites, scramble togeth-er, and cook until done. Serve with 2 slices ofreduced sodium turkey bacon, 1/2 whole wheatEnglish muffin, and 1 peach.Snack1 oz low-fat cheese1 appleLunchTuna & Spinach SaladClean 2 cups raw spinach and place in bowl.Add 1/2 can water-packed tuna. Chop and mixin, 1 stalk celery, 5 mushrooms, 1/2 cucumber,1/2 medium tomato, and 1 tbs vinaigrette dress-ing. Serve with a 1/2 whole wheat pita.Snack10 almonds1/2 cup raisinsDinnerChinese ChickenCube 4 oz boneless chicken breast. Mix chick-en, 1 cup broccoli, and 1 tbs low-sodium soysauce in non-stick pan and sauté until done.Serve with 2 cups lettuce salad with 1 tbs vinai-grette dressing.

DAY 2BreakfastOatmeal, Egg Whites, and FruitMake 1/2 cup cooked oatmeal and place inbowl. Sprinkle with 1/2 fresh cup berries andpour on 1/2 cup skim or soymilk. Serve with 2slices of reduced sodium turkey bacon, 2 scram-bled or hard-boiled egg whites. Snack6 oz plain yogurt1/4 cup fat free granola1/2 bananaLunchHealthy PizzaSpread 5 tbs tomato sauce on 1/2 (separate twosides) whole wheat pita. Sprinkle with 1 ozshredded low-fat cheese and season to taste(ie, oregano, garlic, pepper flakes). Serve with 2cups lettuce salad with 1 tbs vinaigrette dressingand 1 cup cubed melon.

DAY 2 (continued)Snack1 fat free turkey or veggie hot dog 1 tbs mustardDinnerBar-B-Q ChickenMix 1 tsp honey, 1 tbs Mustard, and 3 tbs toma-to sauce together. Spread evenly over 4 ozboneless chicken breast and oven broil or grill.Serve with 1 cup steamed summer squash and1 cup steamed green beans.

DAY 3BreakfastBreakfast BurritoScramble 3 egg whites and wrap in 1/2 of a 12”whole wheat tortilla with 1/2 cup canned blackbeans and 1/2 cup fresh salsa. Serve with 1/2banana.Snack1 slice whole wheat bread.1 tsp natural peanut butter.LunchChef SaladChop and mix together, 6 slices low-sodium,lean ham lunch meat, 1 slice (1 oz) low-fatcheese, 1 hard-boiled egg, 2 cups lettuce, and 1 tbs vinaigrette. Snack1/2 cup low-fat, low-sodium cottage cheese1 appleDinnerVeggie Burgers Burgers: Cook 2 veggie burgers in pan ormicrowave until completely done.Serve with 1 cup steamed zucchini slices, 1 cupsteamed baby carrots, and 1 low-sodium dillpickle.



lost 7.4 ± 17.62 cm. In English units, thisamounted to a loss of 2.9 inches at thewaist. The large standard deviation wasdue to the variation between men andwomen in girth at the waste. But eachindividual in the study, lost girth andtherefore, the loss was significant (P < 0.01).

The trochanter and the upper thighshowed much smaller changes. Data isshown as the mean and standard devia-tions for the entire group of subjects. Forthe thigh, for example, the loss was only0.35 cm. But as shown in Table 7, therewas an increase in hamstring strengthfrom 31.6 to 45.3 kg, an increase of44.6% in strength. This would have theeffect of increasing thigh circumferencein the face of a weight loss relatedreduction in thigh size. The overall effectwould be a smaller loss in thigh circum-

ference due to the hypertrophy of thighmuscle mass.

While the loss in girth at the glutealsand thigh was smaller than might beexpected for such a loss in weight, it wasstill significant (P < 0.01). But, this is notsurprising since the strength gains werealso large in these muscles. Here,increased muscle mass would negatereductions in girth. For example, musclestrength for the gluteals, which started at37.7 kg, increased by 57.3% after thediet. This would cause a large increase inthe girth of the gluteals due to musclehypertrophy.

As a measure of firmness of thegluteal muscles, as described undermethod, a 1.36 kg weight was appliedagainst a tape to see the resistance topressure of the gluteus maximus musclesmeasured around the trochanters. As

Table 6. Diet Compliance*

Exercise Diet Total %Mean 7.50 8.32 15.82 83.27SD 1.53 1.87 2.61

*Raw scores given for exercise compliance (out of 8 total points), diet compliance (out of 9 total points) and total ofexercise and diet (out of 17 total points) as well as % total compliance for both diet and exercise.

Table 7. Strength Changes in theQuadriceps, Gluteus Maximus andHamstring Muscles*

Quads Hamstring GlutsActive GroupMean 16.00 14.14 16.73SD 19.67 12.63 21.27Signif. 0.01 0.01 0.01Control GroupMean 0.18 2.35 3.53SD 9.12 7.74 12.34Signif. > .05 > .05 > .05

*All measurements are in kg. Quads indicate quadri-ceps; and gluts, gluteus maximus muscles.

Table 8. Girth Change in Upper BodyMuscles Before and After the Program*

Wrist Forearm UpperarmActive GroupMean -0.23 -0.92 -2.24SD 0.73 4.78 7.47Signif > 0.05 < 0.01 < 0.01Control GroupMean 0.14 0.06 -0.38SD 0.34 0.49 1.2Signif > 0.05 > 0.05 > 0.05

All measurements are in cm.



shown in Table 10, there was also a sig-nificant increase (P > 0.05) in the firm-ness of the gluteus maximus muscles topressure, showing increase toning of themuscles. Controls showed no significantdifference.

Finally, as shown in Table 11, theheart rate and blood pressure werereduced in subjects on the diet. Theheart rate showed only a small decreaseamounting to 4.9 beats per minute, butthe loss was significant (P < 0.05).Diastolic blood pressure was statisticallythe same comparing pre- and post dietvalues (P > 0.05). Systolic blood pres-sure was reduced by 8.3 mmHg. This losswas significant (P < 0.01). This was notseen in control subjects, where there

were no significant differences over the10-day period (P > 0.05).

DISCUSSIONWith an ever-increasing incidence ofobesity in the United States, it is no sur-prise that a variety of diets has beendeveloped to reduce body weight.32

These diets include the Atkins diet,South Beach diet, high protein diets, lowprotein diets, and every possible varia-tion. But, losing weight involves not justreducing calories but increasing exercise.It has been well documented that duringand after exercise, basil metabolism ofthe body increases for at least 30 min-utes adding to the weight loss associatedwith a dietary program.13 Also, individu-als with high aerobic capacities have alarger thermogenic response than peo-ple with low aerobic capacities.14 Thisincreases thermogenesis, which can bemaintained after aerobic exercise for 12hours or more and adds to the weightloss process.15

In the present investigation, a mixeddiet was used of approximately 1200kcal per day was used. This diet resultedin a deficit of at least 500 to 1000 kcalper day and therefore, in itself shouldcause a weight loss. The fact that musclestrength increased while girth decreased,

Table 9. Girth Change in Lower Body Muscles*

umb umb+1 umb+2 umb-1 umb-2 gluts troch thighActive GroupMean -4.28 -7.40 -2.81 -5.42 -1.10 -0.35 -0.35 -0.35SD 6.58 17.62 2.99 19.42 3.85 3.54 3.54 2.58Sig < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01 < 0.01Control GroupMean 0.52 -0.24 -0.09 0.38 0.11 0.02 0.03 -0.01SD 2.09 3.04 2.86 1.79 2.69 1.10 1.40 3.46Sig > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05

*The measurements are in cm. Umb indicates umbilicus; umb+1, 1 inch above the umbilicus; umb+2,2 inches above the umbilicus; umb-1, 1 inch below the umbilicus; umb-2, 2 inches below the umbili-cus; troch, at the trochanter; and thigh, at mid-thigh.

Table 10. Changes in Blood Pressure andHeart Rate

Change Change ChangeHeart Rate Sys BP Dia BPBPM mm Hg mm Hg

Active GroupMean -4.9 -8.3 -1.1SD 6.4 7.4 5.7Control GroupMean 0.2 0.1 -0.9SD 5.9 8.2 6.9



points to the fact that the diet and exer-cise program were both effective.Subjects maintained high compliance,above 80% in all cases. Thus, for subjectson this diet it can only be presumed thatcompliance was high because the dietitself minimized hunger through its lowlipid composition. Further, the increasein muscle strength over only a ten-dayperiod showed the fitness potential ofthis particular videotape exercise regimein increasing muscle strength andendurance for the lower portion of thebody. The best toning was observed inthe gluteus maximus muscles, where themuscle became highly resistant todepression by force demonstratingincreased toning in these and, likely,other muscles in the body.

The cardiovascular changes, princi-pally the reduction in systolic bloodpressure, show the cardiovascular bene-fits of the exercise. For such a short peri-od of time, there was a significant loss instress on the heart and arteries, due toan 8% loss in systolic blood pressure.Part of the loss can be attributed toweight loss, but the small magnitude ofthe weight loss makes this unlikely. In allprobability, the dynamic exercise pro-gram was responsible for most of thecardiovascular effects. A good aerobicexercise program offers little strengthtraining but a significant benefit on thecardiovascular system. And yet in thepresent investigation, strength didincrease. The inescapable conclusion isthat this program also accomplishedstrength training. When dynamic exer-cise is conducted slowly and against amoderate load, strength training is possi-ble during dynamic exercise.33,34 This iscertainly the case here. High resistancedynamic exercise, as seen here, has ahigh static exercise component, whichfatigues muscle strength and builds mus-cle mass.35

In summary, a proper diet and exer-

cise program involving a mixed diet witha low glycemic index in the presentinvestigation is shown to be ample andadequate means of increasing musclestrength, reducing weight and girth, andincreasing tone in the lower part of thebody. Certainly, the psychologicalaspects of weight loss here are signifi-cant. The fact that almost 2 clothing sizescan be lost in a 10-day period wouldlead to the high compliance we saw herefor the program. With the ever increas-ing emphasis on high fat diets andAtkins approved food, it would appearthat weight could be lost just as well andmuscle increased just by moderatingintake on a mixed diet with adequateexercise program.

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