Resting energy metabolism and cardiovascular disease risk in resistance-trained and aerobically trained males

Training Specificity for Athletes: Emphasis on Strength-Power Training: A Narrative Review

Specificity has two major components: A strength-endurance continuum (S-EC) and adherence to principles of Dynamic Correspondence. Available evidence indicates the existence of the S-EC continuum from two aspects. Indeed, the S-EC exists, particularly if work is equated as a high load low repetition scheme at one end (strength stimulus) and high volume (HIEE stimulus) at the other. Furthermore, some evidence also indicates that the continuum as a repetition paradigm with high-load, low repetition at one end (strength stimulus) and a high repetition, low load at the other end. The second paradigm is most apparent under three conditions: (1) ecological validity-in the real world, work is not equated, (2) use of absolute loads in testing and (3) a substantial difference in the repetitions used in training (for example 2-5 repetitions versus ≥10 repetitions). Additionally, adherence to the principles and criteria of dynamic correspondence allows for greater "transfer of training" to performance measures. Typically, and logically, in order to optimize transfer, training athletes requires a reasonable development of capacities (i.e., structure, metabolism, neural aspects, etc.) before more specific training takes place.

Aerobic training associated with an active lifestyle exerts a protective effect against oxidative damage in hypothalamus and liver: The involvement of energy metabolism

BACKGROUND

Oxidation resistance protein 1 (OXR1) is of scientific interest due its role in protecting tissues against oxidative stress, DNA mutations and tumorigenesis, but little is known regarding strategies to increase OXR1 in different tissues. As an improved antioxidant defense may result from a high total amount of physical activity, the present study was designed to determine whether an active lifestyle including aerobic training exercise and spontaneous physical activity (SPA) can increase OXR1. We have built a large cage (LC) that allows animals to move freely, promoting an increase in SPA in comparison to a small cage (SC).

METHODS

We examined the effects of aerobic training applied for 8 weeks on SPA and OXR1 of C57BL/6 J mice living in two types of housing (SC and LC). OXR1 protein was studied in hypothalamus, muscle and liver, which were chosen due to their important role in energy and metabolic homeostasis.

RESULTS

LC-mice were more active than SC-mice as determined by SPA values. Despite both trained groups exhibiting similar gains in aerobic capacity, only trained mice kept in a large cage (but not for trained mice housed in SC) exhibited high OXR1 in the hypothalamus and liver. Trained mice housed in LC that exhibited an up-regulation of OXR1 also were those who exhibited an energy-expensive metabolism (based on metabolic parameters).

CONCLUSIONS

These results suggest that aerobic training associated with a more active lifestyle exerts a protective effect against oxidative damage and may be induced by changes in energy metabolism.

Resting Energy Expenditure of Master Athletes: Accuracy of Predictive Equations and Primary Determinants

Resting energy expenditure (REE) is determined mainly by fat-free mass (FFM). FFM depends also on daily physical activity. REE normally decreases with increased age due to decreases in FFM and physical activity. Measuring REE is essential for estimating total energy expenditure. As such, there are a number of different equations in use to predict REE. In recent years, an increasing number of older adults continue to participate in competitive sports creating the surge of master athletes. It is currently unclear if these equations developed primarily for the general population are also valid for highly active, older master athletes. Therefore, we tested the validity of six commonly-used equations for predicting REE in master athletes. In conjunction with the World Masters Athletic Championship in Malaga, Spain, we measured REE in 113 master athletes by indirect calorimetry. The most commonly used equations to predict REE [Harris & Benedict (H&B), World Health Organization (WHO), Müller (MÜL), Müller-FFM (MÜL-FFM), Cunningham (CUN), and De Lorenzo (LOR)] were tested for their accuracies. The influences of age, sex, height, body weight, FFM, training hours per week, phase angle, ambient temperature, and athletic specialization on REE were determined. All estimated REEs for the general population differed significantly from the measured ones (H&B, WHO, MÜL, MÜL-FFM, CUN, all p < 0.005). The equation put forward by De Lorenzo provided the most accurate prediction of REE for master athletes, closely followed by FFM-based Cunningham’s equation. The accuracy of the remaining commonly-used prediction equations to estimate REE in master athletes are less accurate. Body weight (p < 0.001), FFM (p < 0.001), FM (p = 0.007), sex (p = 0.045) and interestingly temperature (p = 0.004) are the significant predictors of REE. We conclude that REE in master athletes is primarily determined by body composition and ambient temperature. Our study provides a first estimate of energy requirements for master athletes in order to cover adequately athletes’ energy and nutrient requirements to maintain their health status and physical performance.

Metabolic rate in sedentary adults, following different exercise training interventions: The FIT-AGEING randomized controlled trial

BACKGROUND & AIMS

This study compares the influence of different exercise training programs on basal metabolic rate (BMR) and fat oxidation, in basal conditions (BFox) and during exercise (MFO), in sedentary, middle-aged adults.

METHODS

The study subjects of this 12 week-long, randomised controlled trial, were 71 middle-aged adults (age 53.5 ± 4.9 years; 52% women). Subjects were randomly assigned to one of the following groups: (1) no exercise, (2) concurrent training based on international physical activity recommendations (PAR group), (3) high intensity interval training (HIIT group), and (4) high intensity interval training plus whole-body electromyostimulation (HIIT + EMS group). Subject BMR, BFox and MFO were determined by indirect calorimetry before and after the intervention.

RESULTS

The HIIT + EMS subjects showed significant increases in BFox following the intervention compared with the control group (all P = 0.043); no such differences were seen in the PAR and HIIT compared with the control group (all P ≥ 0.1). A significant increase in post-intervention MFO was noted for the HIIT and HIIT + EMS group compared to the non-exercise control group (P < 0.05); no such difference was seen in the PAR group compared to the control group (all P ≥ 0.05).

CONCLUSIONS

Twelve weeks of high intensity interval training plus whole-body electromyostimulation may increase the BFox and MFO of middle-aged sedentary adults. These findings have important clinical implications; a well-designed high-intensity interval training program plus whole-body electromyostimulation might be followed to help combat the appearance of chronic metabolic diseases characterized by metabolic inflexibility in middle-aged sedentary adults, though it will be necessary to determine how long the effects last.

Establishing an online physical exercise program for people with hemophilia

BACKGROUND

Hemophilia is a congenital bleeding disorder with an estimated frequency of 1:10,000 births. Repeated joint bleeding is a hallmark of the disorder and leads to painful hemophilic arthropathy. Regular exercise can help improve joint stability and function, reduce the risk of injury and bleeding and improve physical fitness and quality of life. This method paper describes an online training concept aiming to offer access to appropriate exercise instructions for people with hemophilia who are not able to attend regular training at a hemophilia center.

METHODS

The online exercise program is accessible through the homepage of the Department of Physical Medicine, Rehabilitation and Occupational Medicine of the Medical University Vienna as well as through scanning a QR code printed on information material using a smart phone or tablet.

RESULTS

The program contains exercises to improve mobility, coordination, muscular strength and flexibility. A brief introduction is given by a hematologist, a pediatrician and a physiatrist. An introductory video informs about contraindications and essential precautions, such as medical attendance and sufficient factor therapy to consider before starting the training. Another video gives advice on the exercise composition. The demonstrated exercises are explained by a physician and are available for adults and children. To individualize training recommendations and offer further diagnostic tools and physical treatment options as necessary, the Department of Physical Medicine, Rehabilitation and Occupational Medicine of the Medical University of Vienna will establish consultation hours for people with hemophilia.

CONCLUSION

As hemophilia is an orphan disease, patients are mainly treated in specialized centers. For patients who live far from these centers or have limited access to a training there for other reasons, the physical medicine consultation hour and the implementation of online exercise instructions offer individually adapted exercise information for a regular home-based training to benefit from increased physical fitness and joint stability.

Housing conditions modulate spontaneous physical activity, feeding behavior, aerobic running capacity and adiposity in C57BL/6J mice

There is evidence of reduced adiposity in rodents living in a large cages (LC) as compared to animals housed in small cages (SC). Because spontaneous physical activity (SPA) provides an important portion of the total daily energy expenditure, an increase of SPA in rodents kept in LC could explain their reduced body fat accumulation. The relationship between SPA and components of physical fitness (i.e. aerobic and anaerobic fitness and body leanness) has not been previously determined. We examined the effects of eight weeks of LC exposure on SPA, body composition, feeding behavior, as well as aerobic and anaerobic running capacity in adult C57BL/6J mice. Male mice were housed in cages of two different sizes for 8 weeks: a small (SC, n = 10) and large (LC n = 10) cages with 1320 cm² and 4800 cm² floor space, respectively. SPA was measured gravimetrically, and food and water intake were recorded daily. Mice had critical velocity (CV) and anaerobic running capacity (ARC) evaluated at the beginning, middle course (4th week) and at the end of study (8th week). Despite non-significant differences in each week LC-mice were more active than SC-mice by considering all SPA values obtained in the entire period of 8 weeks. The difference in SPA over the whole day was mainly due to light phase activity, but also due to activity at dark period (from 6 pm to 9 pm and from 5 am to 6 am). LC-mice also exhibited higher food and water intake over the entire 8-wk period. LC-mice had lower content of fat mass (% of the eviscerated carcass) than SC-mice (SC: 8.4 ± 0.4 vs LC: 6.3 ± 0.3, p < 0.05). LC-mice also exhibited reduced epididymal fat pads (% of body mass) compared to SC-mice (SC: 1.3 ± 0.1 vs LC: 0.9 ± 0.1, p < 0.05) and retroperitoneal fat pads (SC: 0.4 ± 0.05 vs LC: 0.2 ± 0.02, p < 0.05). The LC-group showed significantly higher critical velocity than SC-group at the fourth week (SC: 14.9 ± 0.6 m·min^-1 vs LC: 18.0 ± 0.3 m·min^-1, p < 0.05) and eighth week (SC: 17.1 ± 0.5 m·min^-1 vs LC: 18.8 ± 0.6 m·min^-1, p < 0.05). Our findings demonstrate that eight weeks of LC housing increases SPA of C57BL/6J mice, and this may lead to reduced fat accumulation as well as higher aerobic fitness. Importantly, our study implies that SC limits SPA, possibly generating experimental artifacts in long-term rodent studies.

Central and peripheral effects of physical exercise without weight reduction in obese and lean mice

To investigate the central (hypothalamic) and peripheral effects of exercise without body weight change in diet-induced obesity (DIO). Twelve-week-old male C57Bl/6 mice received a control (C) or a high-fat diet (H). Half of them had free access to running wheels for 5 days/week for 10 weeks (CE) and HE, respectively). Hypothalamic expression of genes related to energy homeostasis, and leptin (Stat3 and p-Stat3) and insulin (Akt and p-Akt) signaling were evaluated. Glucose and leptin tolerance, peripheral insulin sensitivity, and plasma insulin, leptin and adiponectin were determined. Perigonadal and retroperitoneal fat depots were increased by diet but reduced by exercise despite lack of effect of exercise on body weight. Blood glucose during intraperitoneal glucose tolerance test (ipGTT) was higher and glucose decay during intraperitoneal insulin tolerance test (ipITT) was lower in H and HE compared with C and CE. Exercise increased liver p-Akt expression and reduced fast glycemia. High-fat diet increased plasma insulin and leptin. Exercise had no effect on insulin but decreased leptin and increased adiponectin. Leptin inhibited food intake in all groups. Hypothalamic total and p-Stat3 and Akt were similar amongst the groups despite higher plasma levels of leptin and insulin in H and HE mice. High-fat diet modulated gene expression favoring a positive energy balance. Exercise only marginally changed the gene expression. Exercise induced positive changes (decreased fast glycemia and fat depots; increased liver insulin signaling and adiponectin concentration) without weight loss. Thus, despite reducing body weight could bring additional benefits, the effects of exercise must not be overlooked when weight reduction is not achieved.

Effects of aerobic exercise and resistance training on lipid profiles and inflammation status in patients on maintenance hemodialysis

Physical function limitation is a common disorder in chronic hemodialysis (HD) patients, relating to increased morbidity and mortality. The aim of this study was to determine the effects of aerobic and resistance trainings on blood lipids and inflammation status in HD patients. Out of 30 volunteer males who had been undergoing conventional maintenance HD within an HD unit in Tehran, 21 subjects were enrolled. They were randomly assigned into aerobic exercise group - resistance training group undergoing an 8-week intradialytic exercise program (three times/week) and control group (n = 7, each). Training program consisted of 10-30 min stationary cycling at an intensity of 12-16 out of 20 at the rate of perceived exertion (RPE) of Borg scale in aerobic group and using ankle weights for knee extension, hip abduction and flexions at an intensity of 15-17 out of 20 at the RPE of Borg scale in resistance group. Fasting blood samples for serum biochemistry were drawn at baseline and 8 weeks. The age, HD duration, and physical activity score were 51.6±18.9yrs; 25.1±13.9 mo, and 19.2±7.6, respectively. Diabetes mellitus (43%), hypertension (28%), and obstructive uropathy (14%) were the most common underlying diseases. Aerobic and resistance exercises were correlated with serum creatinine (P< 0.0001 and P<0.001) and hs-CRP levels (P=0.005 and P=0.036) reduction so that aerobic exercise induced more reduction. These exercises had no influence on weight, Kt/V values, serum urea, albumin, hemoglobin, and lipid levels (P>0.05). Both intradialytic aerobic and resistance exercises showed beneficial effects on inflammation status without any influences on serum lipid levels probably due to short duration of the study which was not accompanied with body weight changes. Solute removal had no change during exercise programs. There is a need for more investigation on the role of exercise in HD patients.

Efeitos do treinamento resistido na lipoproteína de baixa densidade

Os benefícios da prática regular do exercício físico estão claramente estabelecidos na literatura. Entretanto, a escolha do tipo de exercício ideal pode ser mais salutar para indivíduos com doenças específicas e patologias associadas. O propósito desta revisão foi verificar se o treinamento resistido (TR) exerce alguma alteração no colesterol da lipoproteína de baixa densidade (LDL-C). Foram observadas grandes diferenças na literatura, dificultando uma conclusão em relação aos benefícios do TR nesta revisão. No entanto, foi visto que o TR pode ser promissor na redução dos níveis de LDL-C, principalmente em homens e mulheres adultos, em pacientes com diabetes mellitus tipo 1 e tipo 2 e em mulheres pré-menopausa, não mostrando diferenças na população idosa. Os autores concluem que o TR é uma boa opção de exercício físico para indivíduos, principalmente quando o treinamento aeróbio (TA) é contraindicado.

Resistance training with soy vs whey protein supplements in hyperlipidemic males

Background

Most individuals at risk for developing cardiovascular disease (CVD) can reduce risk factors through diet and exercise before resorting to drug treatment. The effect of a combination of resistance training with vegetable-based (soy) versus animal-based (whey) protein supplementation on CVD risk reduction has received little study. The study's purpose was to examine the effects of 12 weeks of resistance exercise training with soy versus whey protein supplementation on strength gains, body composition and serum lipid changes in overweight, hyperlipidemic men.

Methods

Twenty-eight overweight, male subjects (BMI 25–30) with serum cholesterol >200 mg/dl were randomly divided into 3 groups (placebo (n = 9), and soy (n = 9) or whey (n = 10) supplementation) and participated in supervised resistance training for 12 weeks. Supplements were provided in a double blind fashion.

Results

All 3 groups had significant gains in strength, averaging 47% in all major muscle groups and significant increases in fat free mass (2.6%), with no difference among groups. Percent body fat and waist-to-hip ratio decreased significantly in all 3 groups an average of 8% and 2%, respectively, with no difference among groups. Total serum cholesterol decreased significantly, again with no difference among groups.

Conclusion

Participation in a 12 week resistance exercise training program significantly increased strength and improved both body composition and serum cholesterol in overweight, hypercholesterolemic men with no added benefit from protein supplementation.

A comparison of aerobic exercise and resistance training in patients with and without chronic kidney disease

The morbidity and mortality associated with chronic kidney disease (CKD) are primarily caused by atherosclerosis and cardiovascular disease, which may be in part caused by inflammation and oxidative stress. Aerobic exercise and resistance training have been proposed as measures to combat obesity, inflammation, endothelial dysfunction, oxidative stress, insulin resistance, and progression of CKD. In non-CKD patients, aerobic exercise reduces inflammation, increases insulin sensitivity, decreases microalbuminuria, facilitates weight loss, decreases leptins, and protects against oxidative injury. In nondialysis CKD, aerobic exercise decreases microalbuminuria, protects from oxidative stress, and may increase the glomerular filtration rate (GFR). Aerobic exercise in hemodialysis patients has been reported to enhance insulin sensitivity, improve lipid profile, increase hemoglobin, increase strength, decrease blood pressure, and improve quality of life. Resistance training, in the general population, decreases C-reactive protein, increases insulin sensitivity, decreases body fat content, increases insulin-like growth factor-1 (IGF-1), and decreases microalbuminuria. In the nondialysis CKD population, resistance training has been reported to reduce inflammation, increase serum albumin, maintain body weight, increase muscle strength, increase IGF-1, and increase GFR. Resistance training in hemodialysis increases muscle strength, increases physical functionality, and improves IGF-1 status. Combined aerobic exercise and resistance training during dialysis improves muscle strength, work output, cardiac fitness, and possibly dialysis adequacy. There is a need for more investigation on the role of exercise in CKD. If the benefits of aerobic exercise and strength training in non-CKD populations can be shown to apply to CKD patients as well, renal rehabilitation will begin to play an important role in the approach to the treatment, prevention, and slowed progression of CKD.

Validation of three predictive equations for basal metabolic rate in adults

Objective

To cross-validate three predictive set of equations for basal metabolic rate (BMR) developed by Schofield (Schofield database), Henry (Oxford database) and Cole (Oxford database) using mean values for age, weight, height and BMR of published studies.

Design

Literature review of studies published from 1985 to March 2002.

Setting

All studies selected used appropriate methods and followed conditions that met the criteria established for basal metabolism, were performed in healthy adults, and were not part of the Schofield or Oxford database.

Subjects

A total of 261 groups of men and women from 175 studies were selected and categorised in three age groups (18.5–29.9, 30.0–59.9, ≥60 years old) and three body mass index (BMI) groups (normal weight, overweight and obese).

Results

Linear regression and concordance correlation analysis showed that the three sets of equations had the same association and agreement with measured BMR, across gender, age, and BMI groups. The agreement of all equations was moderate for men and poor for women. The lowest mean squared prediction errors (MSPRs) were given by Henry equations in men and Cole equations in women. Henry and Cole equations gave lower values than Schofield equations, except for men over 60 years of age. Henry equations were the most accurate in men. None of the three equations performed consistently better in women.

Conclusion

These results support the use of Henry equations in men with a wide range of age and BMI. None of the proposed predictive equations seem to be appropriate to estimate BMR in women.

Participation in a behavioral weight-loss program worsens the prevalence and severity of underreporting among obese and overweight women

Underreporting of energy intake is a serious and pervasive problem, especially among women with overweight and obesity. The aim of this study was to determine if the prevalence and severity of underreporting changed after participating in a behavioral weight-loss program. Women with overweight and obesity (N=156, mean age 39.4 years, mean body mass index 31.9) completed a 6-month behavioral weight-loss program. Basal metabolic rate, physical activity level, and energy intake from 7-day food records were collected at baseline and 6 months. The major finding was that underreporting significantly increased in prevalence (39.7% vs 60.3%; P<.001), as did severity of misreporting (-105+/-583 vs -415+/-504 kcal/day; P<.001) following the behavioral weight-loss program. Thus, after completing a behavioral weight-loss program, the prevalence of underreporting and severity of misreporting became significantly worse among women with overweight and obesity.

Mitochondrial function, energy expenditure, aging and insulin resistance

Mitochondria are the cells' powerhouse that produce the ubiquitous energy currency (ATP) by consuming oxygen, producing water and building up the proton motive force. Oxygen consumption is a classical means of assessing energy expenditure, one component of energy balance. When energy balance is positive, weight increases. This is observed during the dynamic phase of obesity, and during body composition changes associated with aging. Whether intrinsic defaults in mitochondria occur is the matter of this review. Indeed, the ratio of ATP over oxygen consumed, which is not fixed, is one way of regulating heat release and ATP flux, but can also be the consequence of environmental conditions of mitochondrial work. For example, various hormones (T3, glucocorticoids), changes in lipid membrane composition, changes in food intake and exercise, and various drugs, can modify the ratio of ATP over oxygen consumed. Aging and insulin resistance are other regulators of this ratio. Finally there is a rising body of evidence linking diabetes to mitochondrial functions.

Exercise and Green Tea Extract Stimulate Fat Oxidation and Prevent Obesity in Mice

INTRODUCTION/PURPOSE

The purpose of the present study was to explore the combined effects of dietary supplementation with green tea extract (GTE) and regular exercise on the development of obesity in high fat-fed C57BL/6J mice.

METHODS

Weight and age-matched male mice were divided into 5 groups of 10 mice each. Groups were treated as follows: a low-fat diet and not exercised (LF), a high-fat diet and not exercised (HF), a high-fat diet supplemented with GTE and not exercised (GTE-HF), a high-fat diet and exercised regularly (EX-HF), or a high-fat diet supplemented with GTE and exercised regularly (GTEEX-HF). The exercise modality was treadmill running.

RESULTS

After 15 wk, GTE alone and regular exercise alone caused a 47 and 24% reduction in body weight gain induced by the high-fat diet, respectively, and when combined, resulted in an 89% reduction. In visceral fat accumulation, GTE alone, exercise alone, and their combination caused a 58, 37, and 87% reduction, respectively. Indirect calorimetry showed that the GTEEX-HF group had the highest energy expenditure and fat utilization in the sedentary condition after 4 wk. Furthermore, the GTEEX-HF group utilized more fat than the EX-HF group during exercise. GTE supplementation increased hepatic fatty acid oxidation both in the exercised and nonexercised groups. In addition, when combined with regular exercise, GTE supplementation also stimulated skeletal muscle fatty acid oxidation.

CONCLUSION

In conclusion, dietary GTE and regular exercise, if combined, stimulate fat catabolism not only in the liver but also in skeletal muscle, and attenuate high-fat diet-induced obesity more effectively than each alone in C57BL/6J mice.

Resting metabolic rate and post-prandial thermogenesis by level of aerobic power in older athletes

1. The aim of the present study was to evaluate the resting metabolic rate (RMR) and thermogenic effect of a meal (TEM) in older athletes. 2. Eighteen older male volunteers were divided into three groups according to their aerobic power related to fat-free mass (FFM) as follows: (i) group I, high aerobic power (Vo(2max) > 70 mL/kg FFM per min); (ii) group II, moderate aerobic power (Vo(2max) = 55-70 mL/kg FFM per min); and (iii) group III, low aerobic power (Vo(2max) < 55 mL/kg FFM per min). 3. The RMR values, covariated for FFM using analysis of covariance (ancova), were higher in group I (mean (+/-SEM) 1.09 +/- 0.04 kcal/min) than in groups II and III (0.99 +/- 0.05 and 0.91 +/- 0.03 kcal/min, respectively). Group I had a tendency for higher mean TEM values compared with the other groups, but the differences were not statistically significant for absolute or percentage values. 4. Master endurance athletes with high aerobic power exhibit a higher RMR than master endurance athletes of similar age and body composition but with lower aerobic power.

Training principles: evaluation of modes and methods of resistance training--a coaching perspective

Current information and evidence indicate that for most activities free weight training can produce superior results compared to training with machines, particularly when the free weight training involves complex, multi-joint exercises. A number of reasons can account for the superiority of free weights; the major factor deals with mechanical specificity. Mechanical specificity is concerned with appropriate movement patterns, force application and velocity of movement. Considering the available evidence that adherence to the concept of specificity of exercise and training can result in a greater transfer of training effect then free weights should produce a more effective training transfer. Therefore, the majority of resistance exercises making up a training programme should include of free weight exercises with emphasis on mechanical specificity (i.e. large muscle mass exercises, appropriate velocity, contraction type etc.). Generally, machines should be used as an adjunct to free weight training and, depending upon the sport, can be used to a greater or lesser extent during various phases of the training period (preparation, pre-competition, competition).

Effect of resistance exercise on postprandial lipemia

The purpose of this study was to examine the effect of resistance exercise on postprandial lipemia. Fourteen young men and women participated in each of three treatments: 1) control (Con), 2) resistance exercise (RE), and 3) aerobic exercise (AE) estimated to have an energy expenditure (EE) equal that for RE. Each trial consisted of performing a treatment on day 1 and ingesting a fat-tolerance test meal 16 h later (day 2). Resting metabolic rate and fat oxidation were measured at baseline and at 3 and 6 h postprandial on day 2. Blood was collected at baseline and at 0.5, 1, 2, 3, 4, 5, and 6 h after meal ingestion. RE and AE were similar in EE [1.7 +/- 0.1 vs. 1.6 +/- 0.1 (SE) MJ, respectively], as measured by using the Cosmed K4b(2). Baseline triglycerides (TG) were significantly lower after RE than after Con (19%) and AE (21%). Furthermore, the area under the postprandial response curve for TG, adjusted for baseline differences, was significantly lower after RE than after Con (14%) and AE (18%). Resting fat oxidation was significantly greater after RE than after Con (21%) and AE (28%). These results indicate that resistance exercise lowers baseline and postprandial TG, and increases resting fat oxidation, 16 h after exercise.

Impact of interviewer's body mass index on underreporting energy intake in overweight and obese women

OBJECTIVE

To determine if overweight and obese women provide more accurate reports of their energy intake by 1) in-person recall with an obese interviewer, 2) in-person recall with a lean interviewer, or 3) telephone recall with an unknown interviewer.

RESEARCH METHODS AND PROCEDURES

Eighty-eight overweight and obese women participated in this study. Subjects completed one telephone-administered multiple-pass 24-hour recall (MP24R) with an unknown interviewer and were then randomly assigned to an in-person MP24R with either a lean or obese interviewer to gather reported energy intake (rEI). Basal metabolic rate (BMR) was measured using a Deltrac monitor, and physical activity (EEPA) was estimated using a Caltrac accelerometer. Therefore, estimated energy expenditure was determined by: estTEE = (BMR + EEPA) x 1.10.

RESULTS

No significant differences were found between the two in-person interview modes for subject age, weight, body mass index, percentage of body fat, total energy expenditure, rEI, and misreporting of energy intake. In-person recall data were combined for comparison with the telephone recalls. No significant difference was found between the in-person and telephone recalls for rEI and misreporting. Mean reported energy intake was significantly lower than estimated total energy expenditure for the telephone recalls and combined (lean and obese modes) in-person recalls.

CONCLUSIONS

This study found that interviewer body mass index had no impact on self-reported energy intake during an in-person MP24R, and that telephone recall data were comparable with in-person recalls. Underreporting was a widespread problem ( approximately 26%) for all modes in this sample.

Safety and efficacy of resistive training in patients with coronary heart disease

In the past 10 to 15 years, there have been several studies on the acute and chronic responses to resistive training in patients with cardiovascular disease. As a result, the safety and efficacy of resistive exercise has become more evident. Resistive training appears to be safe and effective for promoting fitness and improving risk factors in patients with coronary heart disease. This review addresses the health and fitness benefits in these patients, the established guidelines regarding inclusion and exclusion into programs, guidelines for resistive training exercise prescriptions, and how these guidelines have evolved in recent years. (c) 2000 by CHF, Inc.

Characterization of control and immobilized skeletal muscle: an overview from genetic engineering

To elucidate the molecular basis of muscle atrophy, we have performed the serial analysis of gene expression (SAGE) method with control and immobilized muscles of 10 rats. The genes that expressed >0.5% in muscle are involved in the following three functions: 1) contraction (troponin I, C and T; myosin light chain 1-3; actin; tropomyosin; and parvalbumin), 2) energy metabolism (cytochrome c oxidase I and III, creatine kinase, glyceraldehyde-3-phosphate-dehydrogenase, phosphoglycerate mutase, ATPase 6, and aldolase A), and 3) housekeeping (lens epithelial protein). Muscle atrophy appears to be caused by changes in mRNA levels of specific regulators of proteolysis, protein synthesis, and contractile apparatus assembling, such as polyubiquitin, elongation factor 2, and nebulin. Immobilization has produced a decrease more than threefold in gene expression of enzymes involved in energy metabolism, especially ATPase, cytochrome c oxidase, NADH dehydrogenase, and protein phosphatase 1. Differential gene expressions of selenoprotein W and uroporphyrinogen decarboxylase, which can be involved in oxidative stress, were also observed. Other genes with various functions, such as cholesterol metabolism and growth factors, were also differentially expressed. Moreover, novel genes regulated by immobilization were discovered. Thus, the current study allows a better understanding of global muscle characteristics and the molecular mechanisms of sedentarity and sarcopenia.

Strength training in the elderly: effects on risk factors for age-related diseases

Strength training (ST) is considered a promising intervention for reversing the loss of muscle function and the deterioration of muscle structure that is associated with advanced age. This reversal is thought to result in improvements in functional abilities and health status in the elderly by increasing muscle mass, strength and power and by increasing bone mineral density (BMD). In the past couple of decades, many studies have examined the effects of ST on risk factors for age-related diseases or disabilities. Collectively, these studies indicate that ST in the elderly: (i) is an effective intervention against sarcopenia because it produces substantial increases in the strength, mass, power and quality of skeletal muscle; (ii) can increase endurance performance; (iii) normalises blood pressure in those with high normal values; (iv) reduces insulin resistance; (v) decreases both total and intra-abdominal fat; (vi) increases resting metabolic rate in older men; (vii) prevents the loss of BMD with age; (viii) reduces risk factors for falls; and (ix) may reduce pain and improve function in those with osteoarthritis in the knee region. However, contrary to popular belief, ST does not increase maximal oxygen uptake beyond normal variations, improve lipoprotein or lipid profiles, or improve flexibility in the elderly.

Regional body composition determined by dual-energy X-ray absorptiometry. Relation to training, sex hormones, and serum lipids in male long-distance runners

This study investigated the regional distribution of fatty and lean tissue in long-distance runners, and the relation to training, sex hormones, and serum lipids. One hundred and twenty lean men (22 elite, 86 recreational runners and 12 non-running controls) aged 32 +/- 8.1 years (mean +/- SD) participated. Body composition (adipose and lean tissue) was measured by dual-energy x-ray absorptiometry in the total body and in the abdomen, the arms and the legs. Regional and total body fat correlated inversely with the performance at an incremental treadmill exercise test (-0.61 < r < -0.52, P < 0.0001), and the fat percentage in the abdomen and in the legs was 42% and 36% lower in the elite runners in comparison with the non-running controls. Sex hormonal status and serum lipids were unrelated to training. After multiple regression analysis the most significant determinant of the fat percentage in the legs was the weekly distance run (partial r = -0.40, P < 0.0001), whereas in the abdominal region the free testosterone index also contributed strongly (partial r = 0.39, P < 0.0001). In conclusion, long-distance runners had very low amounts of fatty tissue in the abdomen and in the extremities, and the fat percentages in the abdomen and in the legs were associated with both the training intensity and androgenic activity. Since the abdominal fatty tissue is a significant risk factor for cardiovascular disease, running may have a positive impact on the long-term risk.

Safety and efficacy of weight training soon after acute myocardial infarction

BACKGROUND

To determine if weight training used during cardiac rehabilitation as soon as 4 weeks after myocardial infarction (MI) is safe, and if weight training combined with aerobic exercise improves aerobic fitness and muscle strength more than aerobic exercise alone.

METHODS

Twenty-three men within 6 weeks of an acute MI and without exercise-induced ischemia, complex arrhythmias, anterior Q wave MI, or ejection fraction < 40% were randomly assigned to combined weight and cycle training versus cycle training for 10 weeks. The main measures were change in maximal oxygen uptake (VO2max), muscle strength, resting left ventricular (LV) wall segment motion and early diastolic filling by resting echocardiograms, exercise ECG, heart rate, and blood pressure responses [corrected].

RESULTS

VO2max increased 14% (P < 0.01) and cycle time increased 10% (P < 0.01) in the combined training group. The 8% increases in VO2max (P = 0.15) and cycle time (P = 0.08) in the cycling group were not significant. Arm and leg strength increased (P < 0.01) in each group. However, the change was greater for the combined training group--31% versus 16% (P < 0.03) for leg strength and 20% versus 10% (P < 0.001) for arm strength. There were no changes for either group in resting hemodynamics, body weight and composition, LV wall segment motion, LV fractional shortening, and early diastolic function, and no adverse clinical events or exercise-related complications.

CONCLUSIONS

Combined training soon after MI improved aerobic and muscle fitness more than cycling alone, and was performed without complication.

Body fat distribution predicts cardiac risk factors in older female coronary patients

BACKGROUND

After myocardial infarction, women have higher rates of recurrent coronary events than men. This is caused, at least in part, by a higher prevalence of obesity-related coronary risk factors such as hyperlipidemia, hypertension, sedentary lifestyle, insulin resistance, and diabetes. We studied the relationship between measures of body fat distribution, body composition, aerobic fitness, and dietary intake and several coronary risk factors including lipids, glucose, and insulin levels.

METHODS

The study population included 20 women > 60 years of age with recently diagnosed coronary heart disease and a comparison group of 50 healthy women with low-risk coronary risk profiles. Dependent variables included lipid subfractions (fasting, triglycerides, high-density lipoprotein [HDL] cholesterol, and low-density lipoprotein [LDL] cholesterol), glucose levels, and serum insulin levels.

RESULTS

Waist-to-hip ratio (WHR) was the best predictor of serum triglyceride levels (r = .65, P = .002), HDL cholesterol level (r = .46, P = .05), and fasting serum insulin levels (r = .76, P < .001) whereas peak oxygen consumption (Peak VO2) was the best predictor of LDL cholesterol (r = .73, P < .001). In a combined population of the 20 coronary patients and 50 healthy age-matched controls, WHR remained the best predictor of serum triglyceride levels (r = .57, P < .001) and insulin levels (r = .63, P < .001) and Peak V02 was the best predictor of HDL (r = .40, P < .001) and LDL cholesterol (r = .57, P = .004).

CONCLUSIONS

Body fat distribution and peak aerobic fitness, both modifiable factors, are significant predictors of risk factors for second coronary events in older female coronary patients.

Relationship between maximum aerobic power and resting metabolic rate in young adult women

The literature is inconclusive as to the chronic effect of aerobic exercise on resting metabolic rate (RMR), and furthermore there is a scarcity of data on young women. Thirty-four young women exhibiting a wide range of aerobic fitness [maximum aerobic power (VO2max) = 32.3-64.8 ml.kg-1.min-1] were accordingly measured for RMR by the Douglas bag method, treadmill VO2max, and fat-free mass (FFM) by using Siri's three-compartment model. The interclass correlation (n = 34) between RMR (kJ/h) and VO2max (ml.kg-1.min-1) was significant (r = 0.39, P < 0.05). However, this relationship lost statistical significance when RMR was indexed to FFM and when partial correlation analysis was used to control for FFM differences. Furthermore, multiple linear-regression analysis indicated that only FFM emerged as a significant predictor of RMR (kJ/h). When high- (n = 12) and low-fitness (n = 12) groups were extracted from the cohort on the basis of VO2max scores, independent t-tests revealed significant between-group differences (P < 0.05) for RMR (kJ.kg-1.h-1) and VO2max (ml.kg-1.min-1) but not for RMR (kJ/h), RMR (kJ.kg FFM-1.h-1), and FFM. Analysis of covariance of RMR (kJ/h) with FFM as the covariate also showed no significant difference (P = 0.56) between high- and low-fitness groups. Thus the results suggest that 1) FFM accounts for most of the differences in RMR between subjects of varying VO2max values and 2) the RMR per unit of FFM in young healthy women is unrelated to VO2max.

Effect of an 18-wk weight-training program on energy expenditure and physical activity

The purpose of this study was to examine the effect of an 18-wk weight-training program on average daily metabolic rate (ADMR). Before the intervention and in weeks 8 and 18 (T0, T8, and T18, respectively) data on body composition, sleeping metabolic rate (SMR), food intake, energy cost of the weight-training program (EEex), and nontraining physical activity (accelerometer) were collected in the exercise group (EXER, n = 18 males). ADMR was determined in a subgroup (EX12, n = 12) by using doubly labeled water. At T0 and T18, data (except ADMR) were also collected in a control group (Con, n = 8). Body mass did not change in EXER or Con. Fat-free mass increased only in EXER with 2.1 +/- 1.2 kg, whereas fat mass decreased in EXER as well as Con (2.0 +/- 1.8 and 1.4 +/- 1.0 kg, respectively). Initial ADMR (12.4 +/- 1.2 MJ/day) increased at T8 (13.5 +/- 1.3 MJ/day, P < 0.001) with no further increase at T18 (13.5 +/- 1.9 MJ/day). SMR did not change in EXER (4.8 +/- 0.5, 4.9 +/- 0.5, 4.8 +/- 0.5 kJ/min) or Con (4.7 +/- 0.4, 4.8 +/- 0.4 kJ/min). Energy intake did not change in EXER (10.1 +/- 1.8, 9.7 +/- 1.8, 9.2 +/- 1.9 MJ/day) or Con (10.2 +/- 2.6, 9.4 +/- 1.8, 10.1 +/- 1.5 MJ/day) and was systematically underreported in EX12 (-21 +/- 14, -28 +/- 18, -34 +/- 14%, P < 0.001). EEex (0.47 +/- 0.20, 0.50 +/- 0.18 MJ/day) could only explain 40% of the increase in ADMR. Nontraining physical activity did not change in both groups. In conclusion, although of modest energy cost, weight-training induces a significant increase in ADMR.

Relationship between physical activity and HDL-cholesterol in healthy older men and women: a cross-sectional and exercise intervention study

We used cross-sectional and exercise intervention studies to examine whether physical activity levels or increases in peak aerobic capacity (peak VO2) explain variation in high density lipoprotein cholesterol (HDL-C) levels in older men and women. In the cross-sectional study, 307 older individuals (169 men; 138 women; 67 +/- 7 years) were characterized for HDL-C, leisure time physical activity, peak VO2, body composition, body fat distribution and dietary intake. HDL-C was 19% higher (P < 0.001) in women (57 +/- 14 mg/dl) versus men (48 +/- 14 mg/dl). Thirty-two percent of the variation in HDL-C in older men was explained by the waist circumference (r2 = 16%), percent dietary intake of alcohol (r2 = 11%), and carbohydrate (r2 = 6%). Waist circumference was also the best predictor of HDL-C in older women, (r2 = 7%); with percent dietary intake of carbohydrate adding an additional 6% to the model. Neither peak VO2 nor leisure time physical activity were independent predictors of HDL-C. Statistical control for the aforementioned variables diminished, but did not abolish gender differences in HDL-C. Thirty-seven older individuals (23 men; 14 women) participated in a 2-month exercise program in which individuals by week eight were expending approximately 900 kcal per week in exercise energy expenditure. Subjects were maintained in energy balance throughout the exercise program. Endurance training significantly increased peak VO2 by 15% in both men and women, and by design, body composition and body fat distribution did not change. No changes in HDL-C levels were noted. In conclusion, variations in leisure time physical activity or increases in peak VO2 are not independent predictors of HDL-C levels in healthy older men and women. Instead, central adiposity, as estimated by the waist circumference, and to a lesser extent, dietary intake of carbohydrate and alcohol, are significant predictors of variation in plasma HDL-C levels. Furthermore, short-term exercise training, generating less than 900 kcal per week in exercise energy expenditure, in the absence of weight loss, fails to influence HDL-C levels.

Cyclic strain upregulates nitric oxide synthase in cultured bovine aortic endothelial cells

In vivo, endothelial cells (EC) are subjected to hemodynamic forces which may influence the production of nitric oxide. This study was designed to examine the effect of cyclic strain on the expression of endothelial nitric oxide synthase (eNOS) in cultured bovine aortic EC. EC were grown on flexible membranes which were subjected to deformation at 60 cycles/min with -5 or -20 kPa of vacuum. This results in an average strain of 6 and 10%, respectively, which is transmitted to the attached cells. Northern blot analysis of total cytosolic RNA demonstrated an increase in eNOS gene expression with both strain regimens but the increase with 10% average strain was greater than that at 6%. Nuclear runoff transcription assays confirmed the induction of eNOS transcripts. Western blot analysis showed an increase in eNOS level after 24 h of cyclic 10% average strain compared with controls or 6% average strain. Immunohistochemical staining of EC for eNOS was increased in the high strain periphery (7-24% strain) of membranes deformed with -20 kPa vacuum. These results demonstrate that cyclic strain upregulates the expression of eNOS transcripts and protein levels in bovine aortic EC thus emphasizing the importance of hemodynamic forces in the regulation of eNOS in vivo.

Effect of sustained resistance training on basal metabolic rate in older women

OBJECTIVE

To determine if basal metabolic rate (BMR) could be elevated in older women undertaking a program of progressive resistance exercise of up to 52-weeks duration.

DESIGN

Randomized controlled trial with subjects assigned to either a control (CO), high-intensity (HI), or low-intensity (LO) training group for 15 weeks. BMR, body composition, energy intake and expenditure, and muscle strength were assessed at baseline and after 15 weeks. Subjects were encouraged to continue in their assigned exercise group for an additional 37 weeks, after which time they were reevaluated.

SETTING

An exercise facility at a medical center.

SUBJECTS

Thirty-six community-dwelling healthy women aged 65 to 79 years.

INTERVENTION

Exercise groups performed three sets of 10 exercises, 3 days/week, at either 80% of one-repetition maximum (1-RM) for seven repetitions (HI) or 40% of 1-RM for 14 repetitions (LO).

MEASURES

BMR by indirect calorimetry, body composition by dual energy X-ray absorptiometry, energy intake and expenditure from 4-day dietary and activity records, and dynamic muscle strength by 1-RM.

RESULTS

Muscle strength increased, on average (+/- SEM), by 40 +/- 6% and 36 +/- 7% in the HI and LO groups after 15 weeks, respectively, compared with 4 +/- 1% in the nonexercising subjects (P = .0001). Fat mass decreased after 15 weeks in LO exercisers by 1.0 kg (P < .05), whereas there was a trend for fat-free mass (FFM) to increase in the HI group by 0.7 kg (P = .08). No change occurred in any group for BMR. From weeks 15 to 52, muscle strength increased a further 9 +/- 2% and 11 +/- 2% in HI and LO groups, respectively, compared with 3 +/- 1% in nonexercisers (P < .005). There was no change in BMR or any body composition parameter during this time period.

CONCLUSIONS

Neither training program significantly altered BMR and both produced only minimal changes in body composition. However, both the HI and LO exercise regimens resulted in similar and substantial gains in upper and lower body muscle strength that persisted over the course of the year. This suggests that either exercise regimen may prove an effective strategy for preventing frailty and maintaining functional independence in older adults.

Training status, resting metabolic rate, and cardiovascular disease risk in middle-aged men

We investigated differences in resting metabolic rate (RMR) and cardiovascular disease risk factors among 86 middle-aged men (36 to 59 years) classified as resistance-trained ([RT] n = 19), aerobic-trained ([AT] n = 37), or untrained ([UT], n = 30) according to habitual exercise patterns. RMR, body composition, body fat distribution, supine blood pressure, maximal aerobic capacity (VO2max), plasma lipid levels, and fasting levels of insulin, glucose, and thyroid hormones were measured. We found that RMR, adjusted for differences in fat-free mass, showed a tendency to be greater in AT men as compared with RT men (P = .09) and was greater in AT men as compared with UT men (P < .05). No differences in RMR were noted between RT and UT men. UT men had higher values for total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and the insulin to glucose ratio and lower values for high-density lipoprotein cholesterol (HDL-C) (all P < .01) as compared with RT and AT men, whereas no differences in these variables were noted between RT and AT men. Supine diastolic blood pressure was lower in RT men as compared with both AT and UT men. Stepwise regression analysis showed that variations in body fatness accounted for the greatest variation in fasting lipid profile, blood pressure, and the insulin to glucose ratio among groups.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of aerobic and anaerobic exercise conditioning on resting metabolic rate and the thermic effect of a meal

This study examined resting metabolic rate (RMR) and thermic effect of a meal (TEM) among athletes who had participated in long-term anaerobic or aerobic exercise. Nine collegiate wrestlers were matched for age, weight, and fat-free weight with 9 collegiate swimmers. Preliminary testing included maximal oxygen consumption, maximal anaerobic capacity (MAnC) for both the arms and the legs, and percent body fat. On two separate occasions, RMR and TEM were measured using indirect calorimetry. VO2max was significantly higher in the swimmers while MAnC was significantly higher in the wrestlers for both the arms and the legs. RMR adjusted for fat-free weight was not significantly different between groups. The differences in total and percentage of TEM between the groups were not statistically significant, and there were no differences in baseline thyroid hormones. These data suggest that despite significant differences in VO2max and WAnT values following long-term aerobic and anaerobic exercise training, resting energy expenditure does not differ between these college athletes.

Exercise conditioning in older coronary patients. Submaximal lactate response and endurance capacity

BACKGROUND

Older coronary patients are at high risk of cardiac disability. Exercise conditioning programs have been demonstrated to improve functional capacity, particularly in younger coronary patients. In this study, the effects of aerobic conditioning on submaximal and maximal indicators of exercise performance were examined in 45 older coronary patients.

METHODS AND RESULTS

Forty-five patients (mean age, 69 +/- 6 years; range, 62 to 82 years) entered 3-month and 12-month (n = 11) endurance training programs. Training effects were assessed during an exhaustive submaximal exercise protocol with measurement of endurance time, serum lactate, perceived exertion, and expired ventilatory measures. Exhaustive endurance time increased by more than 40% (30 +/- 10 to 41 +/- 10 minutes), with associated decreases in serum lactate, perceived exertion, minute ventilation, heart rate, and systolic blood pressure during steady-state exercise. Respiratory exchange ratio during steady-state exercise, an indicator of substrate utilization, decreased, indicating a shift toward greater use of free fatty acids as a metabolic fuel. In a subset of 10 patients, percent body fat was decreased (32 +/- 8% to 29 +/- 10%) over a period of 3 months.

CONCLUSIONS

Older coronary patients respond to aerobic conditioning with remarkable improvements in submaximal endurance capacity, out of proportion to the more modest increases in VO2max. Activities that were exhaustive before training became sustainable for extended periods of time at a lower perceived exertion. Measurements of serum lactate, respiratory exchange ratio, and ventilation during steady-state exercise document that at an identical absolute work load after conditioning, exercise is performed using aerobic substrate to a greater degree, and ventilatory response to a given work load is lessened.