Lawrence A. Golding

A MECHANISM TO EXPLAIN HOW REGULAR EXERCISE MIGHT REDUCE THE RISK FOR CLINICAL PROSTATE CANCER

Epidemiological studies report that regular physical activity can reduce the risk for prostate cancer. This study was conducted to investigate possible mechanisms to explain the epidemiological data. Serum from sedentary controls or men with regular (5 days/week) aerobic exercise was used to stimulate lymph node cancer of the prostate (LNCaP) tumor cells in vitro. Growth and apoptosis were assessed and cell lysate p53, p21 and Bcl-2 proteins measured. Tryphostin was used to block the insulin-like growth factor-I receptor. Exercise serum-stimulated growth was reduced at 2 and 4 days while apoptosis was increased. Tryphostin reduced growth in the control but not in the exercise serum-stimulated samples. Total cell lysate p53 protein was higher in the exercise serum-stimulated cells at both 2 and 4 days. The levels of p21 protein, a downstream effector of p53, were elevated at 2 days but were normal at 4 days. Bcl-2, an antiapoptotic protein, was significantly reduced at 2 days in the exercise serum-stimulated lysates. These results indicate that exercise training alters serum insulin-like growth factor axis factors in vivo that increase LNCaP cellular p53 protein content in vitro leading to reduced growth via p21 and induced apoptosis via the mitochondrial pathway.

Predicting Maximum Oxygen Uptake from a Modified 3-Minute Step Test

Maximum oxygen uptake (V02max) is considered the best indicator ofaerobic fitness. However, because of the strenuous effort required by the participant, measuring V02max is often neither convenient nor safe for some individuals. Instrumentation, adequate facilities and qualified personnel also may limit the measurement ofV02max. As a result, many investigators have attempted to predict V02max accurately from a variety of more convenient modalities, including step tests (Astrand & Rhyming, 1954; Fitchett, 1985; Francis & Brasher, 1992; Francis & Culpepper, 1989;Jette, 1977; Kasch, 1961; Kasch, Phillips, Ross, Carter, & Boyer, 1966; Kline et al., 1987; Siconolfi, Garber, Lasater, & Careleton, 1985; Thomas, Weller, & Cox, 1993; Wyndham, 1967). Step tests vary in stepping frequency, bench height, test duration, the number ofstages, and scoring method, but the main purpose ofall step tests is to assess cardiorespiratory fitness. In 1961, Kasch validated a singlestage step test that used a T-min postexercise recovery heart beat count (HBC) to assess cardiorespiratory fitness. The Kasch Step Test used a 12-inch bench, a stepping rate of 24 steps per minute, and duration of 3 min. Within 5 s after completing the step test, the participant sat on the bench and heartbeats were counted for 1 min. The total heartbeat count was referred to as the

The Effects of Adding Leucine to Pre and Postexercise Carbohydrate Beverages on Acute Muscle Recovery From Resistance Training

Stock, MS, Young, JC, Golding, LA, Kruskall, LJ, Tandy, RD, Conway-Klaassen, JM, and Beck, TW. The effects of adding leucine to pre and postexercise carbohydrate beverages on acute muscle recovery from resistance training. J Strength Cond Res 24(8): 2211-2219, 2010-The present study examined the effects of adding leucine to pre and postexercise carbohydrate beverages on selected markers of muscle damage, delayed-onset muscle soreness (DOMS), and squat performance for up to 72 hours after lower-body resistance training. Seventeen resistance trained men (mean ± SD age 22.9 ± 2.9 years) and 3 resistance trained women (mean ± SD age 21.6 ± 2.6 years) performed 6 sets of squats to fatigue using 75% of the 1 repetition maximum. Each subject consumed a carbohydrate beverage 30 minutes before and immediately after exercise with or without the addition of 22.5 mg·kg−1 (45 mg·kg−1 total) of leucine in a randomized, double-blind fashion. Serum creatine kinase (CK), lactate dehydrogenase (LDH), and DOMS were analyzed immediately before (TIME1), 24 (TIME2), 48 (TIME3), and 72 (TIME4) hours after exercise. The subjects repeated the squat protocol at TIME4 to test recovery. No differences were observed between groups for squat performance, defined as the total number of repetitions performed during 6 sets of squats, for both TIME1 and TIME4. The addition of leucine did not significantly decrease CK and LDH activity or DOMS. These results suggested that adding leucine to carbohydrate beverages did not affect acute muscle recovery and squat performance during both initial testing and during a subsequent exercise bout 72 hours later in resistance trained subjects.

Validity and reliability of a one‐minute half sit‐up test of abdominal strength and endurance

Abdominal muscle strength and endurance are widely assessed by means of a timed 1‐minute full sit‐up test, despite the more accepted use of half sit‐ups as a muscular strength and endurance exercise. In the present study, the validity and reliability of a 1‐minute half sit‐up protocol was investigated. A total of 142 different subjects participated in one of four studies designed to assess test‐retest reliability, interapparatus reliability, intertester reliability, and validity. Findings included very high test‐retest reliability (r = 0.98), moderately high interapparatus reliability (r = 0.71), and high intertester reliability (r = 0.76). The correlation of the half sit‐up test with the full sit‐up test of the National YMCA was 0.67 and the correlation with isometric abdominal strength was 0.38. The proposed half sit‐up test was found to be reliable and is proposed as an alternative method of evaluating abdominal strength and endurance.

Low-Intensity Exercise, Vascular Occlusion, and Muscular Adaptations

The study investigated the effects of low-intensity exercise on muscular fitness when combined with vascular occlusion. Nineteen college male and female students performed two sets of a 5-min step exercise using a 12-inch bench three times per week for 5 weeks. During the step exercise, blood flow to one leg was restricted (vascular occlusion) with a blood pressure cuff, while the other leg was not occluded. Muscular strength of the occluded leg was significantly increased over the nonoccluded leg (p < 0.05). Muscular endurance and muscle mass were improved after 5 weeks of training (p < 0.05); however, the changes between the two legs were not significantly different (p > 0.05). Exercise with vascular occlusion has the potential to be an alternative form of training to promote muscular strength.

Regular Exercise and Plasma Lipid Levels Associated With the Risk of Coronary Heart Disease: A 20-Year Longitudinal Study

We investigated the effects of regular exercise on the plasma lipid levels that contribute to coronary heart disease (CHD), of 20 sedentary men who participated in an exercise program over 20 consecutive years. The men, whose initial ages ranged from 30–51 years, participated in the University of Nevada-based exercise program for an average of 45 min/day, 3.5 days/week. The study examined plasma levels of low-density lipoprotein (LDL) cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), and TC to HDL-C (TC/HDL-C) ratios. All lipid values improved significantly during the study (p < .05). The largest changes occurred during the first year of participation and slow, gradual improvements continued in the subsequent years. We concluded that regular exercise has positive effects on plasma lipid levels, which results in reducing the risk of CHD in middle-aged and older adults.

A Graded Exercise Test Protocol for Spinal Cord Injured Individuals

The purpose of this study was to develop a graded exercise protocol using a wheelchair on the treadmill for lower-limb disabled individuals. Twenty-seven subjects with lower-limb disabilities were assessed with an experimental graded exercise test protocol that stared at 2 mph and 0% grade and progressed by increasing the grade 2% every 3 minutes while keeping the treadmill speed constant. The test protocol was sensitive to varying levels of fitness, enabling all subjects to complete at least three testing stages. The protocol was able to evaluate unfit individuals, while at the same time allowing elite wheelchair athletes to attain maximum heart rate (HR) and oxygen uptake (VO2) values, which they did within 24 minutes of beginning the procedure. The increase in work was gradual enough to be within a medical margin of safety for all subjects, and entailed an increase of approximately one MET per stage. Maximum VO2 and HR values demonstrated the familiar linear relationship associated with work.

Myocardial Stress After Ultra-Endurance Running In Extreme Heat: 1150 Board #5 2:00 PM ??? 3:30 PM

Introduction The effects of prolonged exercise on cardiac muscle integrity and function are still more controversial and less well investigated than skeletal muscle damage. The “Badwaterultra”, a 216 km race through Death Valley, CA, USA, might serve as an excellent model to further investigate cardiac muscle integrity and function (Figure 1). The combination of extreme temperatures of up to 54°C and a demanding course profile consisting of 110.4 flat km, 73.6 uphill km (approx. 4000 m total) and 32 downhill km (approx. 1400 m total) makes it to one of the world toughest Ultramarathons. The purpose of this study was to investigate possible negative effects of prolonged, exhaustive exercise in extreme heat on the heart based upon humoral markers of cardiac damage and dysfunction in experienced ultraendurance runners.

THE EFFECT OF ELECTRICALLY INDUCED STRENGTH TRAINING ON TRICEPS BRACHII STRENGTH IN UNTRAINED FEMALES

Twenty‐seven apparently healthy females volunteered for a study to compare the effect of neuro‐muscular electrical stimulation (NMES) (N = 7), traditional isotonic weight training (N =9) and NMES combined with isotonic weight training (N =11) on triceps brachii strength. Strength was measured isotonically (1‐RM) and isometrically (MVIC). The NMES group received NMES 3 times per week. The Weight and Weight/NMES groups performed 3 sets of 8 to 10 repetitions at 60% of 1‐RM, 3 times per week. All groups were pre‐ and post‐tested to determine 1‐RM and MVIC. Strength was also tested after four weeks, in order to ensure the Weight and NMES/Weight groups were training at a minimum of 60% of 1‐RM. Two mixed factor design ANOVAs (Group x Time x Arm) found no significant difference between groups in a pretest (p ≤ 0.05). All three groups demonstrated a significant absolute increase in strength, both isometrically and isotonically. A statistical difference was not found between the three training methods in their ef...