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Effects of equal-volume resistance training performed one or two times a week in upper body muscle size and strength of untrained young men
Abstract and Figures
Aim:
The purpose of the present study was to compare the effects of equal-volume resistance training (RT) performed once or twice a week on muscle mass and strength of the elbow flexors in untrained young men.
Methods:
Thirty men (23 ± 3 years) without previous resistance training experience were divided into two groups: Group 1 (G1) trained each muscle group only once a week and group 2 (G2) trained each muscle twice a week during 10 weeks. Baseline and 10 weeks post-test elbow flexors muscle thickness (MT) were measured using a B-Mode ultrasound. Peak torque (PT) was assessed by an isokinetic dynamometer before and after the training program.
Results:
Elbow flexors MT increased significantly (P<0.05) from 31.70 ± 3.31 to 33.43 ± 3.46 mm in G1, and from 32.78 ± 4.03 to 35.09 ± 3.55 mm in G2. Elbow flexors PT also increased (P<0.05) from 50.77 ± 9.26 to 54.15 ± 10.79 N.m in G1, and from 48.99 ± 11.52 to 55.29 ± 10.24 N.m in G2. The results of ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT.
Conclusion:
The results from the present study suggest that untrained men experience similar gains in muscle mass and strength with equal volume RT performed one or two days per week.
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... The joint torque for healthy non-athletic participants (w=0) is shown in Table 5. A mean value supplied by [63] for training time per week is represented by ς and is equal to 0.065. According to Ekblom and Bergh [32], the peak muscle torque increases 3% for each skin temperature more than 20 o , no more than 40 o . ...
... When determining the maximum isometric moment-generating capability, we consider the model's maximum activation for MTG. As mentioned in section 3.2, the peak isometric torque at the joints is influenced by various factors, including age [20,22,23], height [20,24,26], body mass [20,24,25], as well as sex, dominant side [27], athletic activity [63], and skin temperature [32]. ...
... The biomechanical joint torque is also subject-specific. The variations in peak torque concerning age [20,22,23], height [20,24,26], body mass [20,24,25], dominant side [27], activity level [63], and skin temperature are modeled based on the literature data. The maximum joint ROM can be affected by sex differences in passive torque function. ...
A musculoskeletal (MSK) model is an important tool for analysing human motions , calculating joint torques during movement, enhancing sports activity, and developing exoskeletons and prostheses. To enable biomechanical investigation of human motion, this work presents an open-source lower body MSK model. The MSK model of the lower body consists of 7 body segments (pelvis, left/right thigh, left/right leg, and left/right foot). The model has 20 degrees of freedom and 28 muscle torque generators, which are developed from experimental data. The model can be modified for different anthropometric measurements and subject body characteristics, including sex, age, body mass, height, physical activity, and skin temperature. The model is validated by simulating the torque within the range of motion of isolated movements; all simulation findings exhibit a good level of agreement with the literature.
... The dominant side can provide a mean value of 9% more strength than the non-dominant side [34,36]. • Physical activity: has an impact on muscle strength [47]. Specifically, adult athletes have significantly higher concentric and eccentric peak strength of most muscles [37]. ...
... In Table 5, the joint torque is reported for healthy non-athletic subjects (w=0 for this group). For the upper-limb, the value of ς is equal to 0.065, which is a mean value reported by [47] for training time per week. ...
... We consider maximum activation for MTG in the model when calculating maximum isometric moment-generating capability. According to section 4.2, the joint peak isometric torque is a function of age [27,29,30], height [27,31,33], body mass [27,31,32], as well as, sex, dominant side [34,36], and athletic activity [47]. ...
A musculoskeletal (MSK) model is a valuable tool for assessing complex biomechanical problems, estimating joint torques during motion, optimizing motion in sports, and designing exoskeletons and prostheses. This study proposes an open-source upper body MSK model that supports biomechanical analysis of human motion. The MSK model of the upper body consists of 8 body segments (torso, head, left/right upper arm, left/right forearm, and left/right hand). The model has 20 degrees of freedom (DoFs) and 40 muscle torque generators (MTGs), which are constructed using experimental data. The model is adjustable for different anthropometric measurements and subject body characteristics: sex, age, body mass, height, dominant side, and physical activity. Joint limits are modeled using experimental dynamometer data within the proposed multi-DoF MTG model. The model equations are verified by simulating the joint range of motion (ROM) and torque; all simulation results have a good agreement with previously published research.
... This aligned with some previous studies demonstrating the sufficiency of low-frequency training for hypertrophy. For example, Gentil and the team demonstrated that after 10 weeks of training, elbow flexor thickness significantly increased by approximately 5.5% from a once-weekly training program [33]. Similarly, another study demonstrated no statistically significant difference in the hypertrophy of the elbow flexors, elbow extensors, and vastus lateralis between groups training three times per week and those training once per week over an eight-week period [34]. ...
This study aimed to investigate the regional hypertrophic effects of two different once-weekly resistance training programs on the quadriceps muscle. Eighteen untrained men (Age: 21.1±0.5 years, Height: 174.1±5.3 cm, Body weight: 68.8±11.3 kg) with no prior resistance training experience were recruited. Participants were randomly assigned to one of two once-weekly training programs: a Mechanical Tension program (TN) or a Mechanical Tension with Metabolic Stress program (TS), both progressively designed over 6 weeks. Quadriceps muscle cross-sectional areas (QCSA) were measured using magnetic resonance imaging (MRI) at three regions—proximal, middle, and distal—before and after training. The finding demonstrated QCSA significantly increased in the proximal region (∆9.97%, ES = Moderate, and ∆8.9%, ES = Moderate), middle region (∆8.19%, ES = Moderate, and ∆8.42%, ES = Moderate), and distal region (∆7.73%, ES = Moderate, and ∆7.76%, ES = Moderate) for the TN and TS groups, respectively. Maximum strength also significantly increased in both group (∆26.83% in TS and ∆19.82% in TN with ES = Large). Additionally, strong to very strong positive correlations were found among the different regions (r = 0.82–0.94, p = 0.000), which may suggest that measuring a single region could be sufficient for those with budgetary constraints. In conclusion, both training programs effectively induced quadriceps hypertrophy, as well as resulting in increased maximum strength, in untrained participants, highlighting the effectiveness of one-weekly training in promoting muscle growth. Additionally, the knee extension exercise demonstrated the ability to induce relatively uniform hypertrophy across all quadriceps regions.
... However, CTAT seems to bring greater adaptations in aerobic power and endurance than CTRT, while CTRT did not show any advantage over CTAT. This suggests that one or two RT sessions per week results in similar benefits, which agrees with previous studies in trained and untrained young people without SCI [37,38]. However, although a weekly session of AT might be sufficient to improve cardiovascular fitness, the results are not optimal when compared with a higher frequency. ...
Background
This study aimed to investigate the effects of different volumes of aerobic training (AT) and resistance training (RT) during a concurrent exercise training program on selected indicators of physical fitness and pulmonary function in women with spinal cord injury (SCI).
Methods
Twenty-three inactive females with complete or incomplete SCI from T6 to L5 were divided into three groups: concurrent training with a focus on AT (CTAT; two weekly sessions of AT and one of RT), concurrent training with a focus on RT (CTRT; two weekly sessions of RT and one of AT), and control (CON). Tests were performed before and after an 8-week experimental period for indicators of pulmonary function, aerobic power, endurance performance, muscular strength and endurance, speed, and change of direction.
Results
Markers of both aerobic and muscular fitness increased in the CTAT and CTRT groups, but not in CON. There were significant differences in aerobic power and endurance performance between the CTAT and CTRT groups, with greater changes in CTAT. Both CTAT and CTRT improved respiratory functions, with no differences between them (p > 0.05).
Conclusions
CTAT and CTRT improved most of the indicators of physical fitness. However, CTAT should be used to achieve higher aerobic power and endurance without compromising muscle strength.
... Isotonic II training group significantly increased in the arm circumference, but little bit change in group I three sessions per week improved in flexed arm girth, much better than control group. P. Gentil et al., [6] suggested that untrained men experience similar muscle girth and strength with equal volume resistance training performed one or two days per week. ...
The purpose of this study was to determine the effects of short-term equal-volume isotonic training with different workout frequency on upper body, lower body, and muscle girth in male volleyball players. Forty-five male volleyball players were randomly selected from Govt. Degree College Killam, affiliated with Kashmir University (UT) Jammu and Kashmir with mean ± SD: (19.45 ± 3.4 years, height of 177.18 ± 4.15 centimetres, 66.70 ± 5.30 kg and BMI 21.20 ± 3.25 were chosen). The subjects were segregated into three groups; total-body isotonic training, (12 exercises for two sessions per week) (Isotonic G-I=15), upper-body, and lower-body isotonic training (12 exercises for three sessions per week) (Isotonic G-II=15), and control group (CG=15) didn't take part in any special training. Assessments of body composition, height, weight, body mass index, and flexed arm girth, strength (one repetition maximum in bench press) and vertical jump were determined before and after 8 weeks of training. Flexed-arm girth, 1-RM bench press and vertical jump was improved significantly in all training groups (P < 0.05). All groups increased body weight and body composition (P ≤ 0.05), but isotonic G-I group showed a little improvement rather than other isotonic G-II. It is concluded that in healthy young men, whole and split weight training routine produce similar results over the first 2 months of training, with minimal differences among groups.
... Isotonic II training group significantly increased in the arm circumference, but little bit change in group I three sessions per week improved in flexed arm girth, much better than control group. P. Gentil et al., [6] suggested that untrained men experience similar muscle girth and strength with equal volume resistance training performed one or two days per week. ...
The purpose of this study was to determine the effects of short-term equal-volume isotonic training with different workout frequency on upper body, lower body, and muscle girth in male volleyball players. Forty-five male volleyball players were randomly selected from Govt. Degree College Killam, affiliated with Kashmir University (UT) Jammu and Kashmir with mean ± SD: (19.45 ± 3.4 years, height of 177.18 ± 4.15 centimetres, 66.70 ± 5.30 kg and BMI 21.20 ± 3.25 were chosen). The subjects were segregated into three groups; total-body isotonic training, (12 exercises for two sessions per week) (Isotonic G-I=15), upper-body, and lower-body isotonic training (12 exercises for three sessions per week) (Isotonic G-II=15), and control group (CG=15) didn't take part in any special training. Assessments of body composition, height, weight, body mass index, and flexed arm girth, strength (one repetition maximum in bench press) and vertical jump were determined before and after 8 weeks of training. Flexed-arm girth, 1-RM bench press and vertical jump was improved significantly in all training groups (P < 0.05). All groups increased body weight and body composition (P ≤ 0.05), but isotonic G-I group showed a little improvement rather than other isotonic G-II. It is concluded that in healthy young men, whole and split weight training routine produce similar results over the first 2 months of training, with minimal differences among groups.
... The ndings of the present study are following other studies that reported changes in muscle size and body composition after ST with varied training frequencies and volume [18,19]. Similarly, other authors reported similar changes in muscle strength and hypertrophy with equal volume ST performed one or two times per week in untrained [20] and trained men [21]. ...
Methods
Seventeen university students (11 girls), 18–21 years old, were randomly divided into two groups: strength training group (ST,n = 12) and control group (CG,n = 5). Anthropometric and body composition measures, one-repetition maximum test, and sleep parameters (Pittsburgh Sleep Quality Index [PSQI], insomnia (Insomnia Severity questionnaire), daytime sleepiness (Epworth Sleepiness Scale [ESS]), and chronotype were evaluated pre and post-intervention. Training consisted of 60 min·d− 1 (2 times/week, for 4-weeks), with 3 sets of 10–12 repetitions, and a 1-minute rest interval between sets and exercises.
Results
The results through a 2 × 2 (time×groups) repeated measures analysis variance demonstrated a significant time effect that improves lower limb performance (F = 11.82;p = < 0.01), with a significant interaction (F = 6.07;p = 0.05), and upper limb performance (F = 3.30;p = 0.025), and there was a significant time effect on the chronotype (F = 4.75;p < 0.05). Individual analyses in ST group, ~ 58.3% presented a reduction in the PSQI score; ~25% no change, and ~ 16. 6% showed an increased score. For the ESS, ~ 25% showed a reduction, ~ 58.3% no change, and ~ 16.6% an increase. In sleep efficiency, ~ 25% increase; ~41.6% a reduction, and ~ 33.3% had no change.
Conclusion
A short-term strength-training program with an increase in weekly load for four weeks is not able to modulate sleep quality, duration, efficiency, daytime sleepiness, or insomnia, independent of intensity, but, had influenced the chronotype.
Background: Weekly set volume and frequency are used to manipulate resistance training (RT) dosage. Previous research has identified higher weekly set volume as enhancing muscle hypertrophy and strength gains, but the nature of the dose-response relationship still needs to be investigated. Mixed evidence exists regarding the effects of higher weekly frequency. Objective: Before meta-analyzing the volume and frequency research, all contributing RT sets were classified as direct or indirect, depending on their specificity to the hypertrophy/strength measurement. Then, weekly set volume/frequency for indirect sets was quantified as 1 for 'total,' 0.5 for 'fractional,' and 0 for 'direct.' A series of multi-level meta-regressions were performed for muscle hypertrophy and strength, utilizing 67 total studies of 2,058 participants. All models were adjusted for the duration of the intervention and training status. Results: The relative evidence for the 'fractional' quantification method was strongest; therefore, this quantification method was used for the primary meta-regression models. The posterior probability of the marginal slope exceeding zero for the effect of volume on both hypertrophy and strength was 100%, indicating that gains in muscle size and strength increase as volume increases. However, both best fit models suggest diminishing returns, with the diminishing returns for strength being considerably more pronounced. The posterior probability of the marginal slope exceeding zero for frequency's effect on hypertrophy was less than 100%, indicating compatibility with negligible effects. In contrast, the posterior probability for strength was 100%, suggesting strength gains increase with increasing frequency, albeit with diminishing returns. Conclusions: Distinguishing between direct and indirect sets appears essential for predicting adaptations to a given RT protocol, such as using the 'fractional' quantification method. This method's dose-response models revealed that volume and frequency have unique dose-response relationships with each hypertrophy and strength gain. The dose-response relationship between volume and hypertrophy appears to differ from that with strength, with the latter exhibiting more pronounced diminishing returns. The dose-response relationship between frequency and hypertrophy appears to differ from that with strength, as only the latter exhibits consistently identifiable effects.
Human motion capture technology is utilized in many industries, including entertainment, sports, medicine, augmented reality, virtual reality, and robotics. However, motion capture data only allows the user to analyze human movement at a kinematic level. In order to study the corresponding dynamics and muscle properties, additional sensors such as force plates and electromyography sensors are needed to collect the relevant data. Collecting, processing, and synchronizing data from multiple sources could be laborious and time-consuming. This study proposes a method to generate the dynamics and muscle properties of existing motion capture datasets. To do so, our method reconstructs motions via kinematics, dynamics, and muscle modeling with a musculoskeletal model consisting of 14 joints, 40 degrees of freedom, and 15 segments. Compared to current physics simulators, our method also infers muscle properties to ensure our human model is realistic. We have met International Society of Biomechanics standards for all terminologies and representations. Furthermore, our integrated musculoskeletal model allows the user to preselect various anthropometric features of the human performing the motion, such as height, mass, level of athleticism, handedness, and skin temperature, which are often infeasible to estimate from monocular videos without appropriate annotations. We apply our method on the Human3.6M dataset and show that our reconstructed motion is kinematically similar to the ground truth markers while being dynamically plausible when compared to experimental data found in literature. The generated data (Human3.6M+) is available for download.
Many individuals do not participate in resistance exercise, with perceived lack of time being a key barrier. Minimal dose strategies, which generally reduce weekly exercise volumes to less than recommended guidelines, might improve muscle strength with minimal time investment. However, minimal dose strategies and their effects on muscle strength are still unclear. Here our aims are to define and characterize minimal dose resistance exercise strategies and summarize their effects on muscle strength in individuals who are not currently engaged in resistance exercise. The minimal dose strategies overviewed were: “Weekend Warrior,” single-set resistance exercise, resistance exercise “snacking,” practicing the strength test, and eccentric minimal doses. “Weekend Warrior,” which minimizes training frequency, is resistance exercise performed in one weekly session. Single-set resistance exercise, which minimizes set number and session duration, is one set of multiple exercises performed multiple times per week. “Snacks,” which minimize exercise number and session duration, are brief bouts (few minutes) of resistance exercise performed once or more daily. Practicing the strength test, which minimizes repetition number and session duration, is one maximal repetition performed in one or more sets, multiple days per week. Eccentric minimal doses, which eliminate or minimize concentric phase muscle actions, are low weekly volumes of submaximal or maximal eccentric-only repetitions. All approaches increase muscle strength, and some approaches improve other outcomes of health and fitness. “Weekend Warrior” and single-set resistance exercise are the approaches most strongly supported by current research, while snacking and eccentric minimal doses are emerging concepts with promising results. Public health programs can promote small volumes of resistance exercise as being better for muscle strength than no resistance exercise at all.
The authors assessed the diet and exercise habits and perceived barriers to following a healthy lifestyle of 471 college students. Sixty percent of the participants were female and 31% had BMIs > 25. Breakfast was the most commonly missed meal and 63% of students snacked one to two times per day. Fifty-eight percent of participants ate vegetables and 64% ate whole or canned fruit less than once per day. Men consumed more soda and alcohol and used higher fat dairy, ate more meat, and ate fewer vegetables and fruits than women. Over half of the subjects rated their diet as poor or fair with “lack of time” listed as the number one barrier to eating well. Men exercised more frequently and at greater intensity than women and were more confident with their body image. The most common barrier to exercise was “lack of time.” The results of this study have implications for the design of general and specific diet and physical activity interventions among college students.
We reviewed the effect of resistance training on blood pressure and other cardiovascular risk factors in adults. Randomized, controlled trials lasting ≥4 weeks investigating the effects of resistance training on blood pressure in healthy adults (age ≥18 years) and published in a peer-reviewed journal up to June 2010 were included. Random- and fixed-effects models were used for analyses, with data reported as weighted means and 95% confidence limits. We included 28 randomized, controlled trials, involving 33 study groups and 1012 participants. Overall, resistance training induced a significant blood pressure reduction in 28 normotensive or prehypertensive study groups [-3.9 (-6.4; -1.2)/-3.9 (-5.6; -2.2) mm Hg], whereas the reduction [-4.1 (-0.63; +1.4)/-1.5 (-3.4; +0.40) mm Hg] was not significant for the 5 hypertensive study groups. When study groups were divided according to the mode of training, isometric handgrip training in 3 groups resulted in a larger decrease in blood pressure [-13.5 (-16.5; -10.5)/-6.1(-8.3; -3.9) mm Hg] than dynamic resistance training in 30 groups [-2.8 (-4.3; -1.3)/-2.7 (-3.8; -1.7) mm Hg]. After dynamic resistance training, Vo(2) peak increased by 10.6% (P=0.01), whereas body fat and plasma triglycerides decreased by 0.6% (P<0.01) and 0.11 mmol/L (P<0.05), respectively. No significant effect could be observed on other blood lipids and fasting blood glucose. This meta-analysis supports the blood pressure-lowering potential of dynamic resistance training and isometric handgrip training. In addition, dynamic resistance training also favorably affects some other cardiovascular risk factors. Our results further suggest that isometric handgrip training may be more effective for reducing blood pressure than dynamic resistance training. However, given the small amount of isometric studies available, additional studies are warranted to confirm this finding.
Objective: A lack of physical activity plays an important role in cardiovascular disease, however the mechanism(s) are poorly understood. In addition, the majority of studies which have examined the relationship between physical activity and arterial function have used subjective measures of activity. The aim of this cross-sectional study was to investigate if objectively measured physical activity is associated with arterial stiffness and wave reflection in patients attending an outpatient hypertension clinic. Design and Method: Physical activity was measured for 7 consecutive days using a triaxial accelerometer (RT3 Stayhealthy). This provides data on estimated energy expenditure in physical activity and time spent in the various intensities of activity. Brachial blood pressure (BP) was measured using an oscillometric technique (Omron) in the right arm. Using the same arm, augmentation index (AIx) and aortic BP were measured using radial applanation tonometry (SphygmoCor). Pulse wave velocity (PWV) was measured using the foot-to-foot method (Artech Medical). Results: Eighty adults (female, n = 40) with a mean ± sd age 49 ± 25y, body mass index (BMI) 29.7 ± 5.1 kg/m2 (n = 70) and waist circumference 101 ± 14 cm (n = 42) participated. PWV was 10.3 ± 2.4m/s (n = 36) and AIx was 27.1 ± 14.4% (n = 48). Physical activity data was available for n=53 patients. Time spent in at least moderate physical activity was 36 ± 31 minutes/d and n = 26 (49%) patients carried out at least 30 minutes/d of at least moderate intensity activity. AIx and aortic BP were significantly lower in those who engaged in higher amounts of vigorous activity (P < 0.01)(n = 48). In stepwise regression analysis, after adjusting for age, gender, BMI, alcohol intake and smoking, the only independent predictors of AIx were physical activity, heart rate and systolic BP. There was no relationship between physical activity and PWV (n = 36). Conclusion: Physical activity reduces aortic wave reflections and BP, independent of BP and age probably because of increased nitric oxide production in the medium sized arteries. This reiterates the importance of regular physical activity in hypertensive patients to maintain optimum wave reflections.
SUMMARY In order to stimulate further adaptation toward specific training goals, progressive resistance training (RT) protocols are necessary. The optimal characteristics of strength-specific programs include the use of concentric (CON), eccentric (ECC), and isometric muscle actions and the performance of bilateral and unilateral single- and multiple-joint exercises. In addition, it is recommended that strength programs sequence exercises to optimize the preservation of exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher-intensity before lower-intensity exercises). For novice (untrained individuals with no RT experience or who have not trained for several years) training, it is recommended that loads correspond to a repetition range of an 8-12 repetition maximum (RM). For intermediate (individuals with approximately 6 months of consistent RT experience) to advanced (individuals with years of RT experience) training, it is recommended that individuals use a wider loading range from 1 to 12 RM in a periodized fashion with eventual emphasis on heavy loading (1-6 RM) using 3- to 5-min rest periods between sets performed at a moderate contraction velocity (1-2 s CON; 1-2 s ECC). When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number. The recommendation for training frequency is 2-3 dIwkj1 for novice training, 3-4 dIwkj1 for intermediate training, and 4-5 dIwkj1 for advanced training. Similar program designs are recom- mended for hypertrophy training with respect to exercise selection and frequency. For loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion with emphasis on the 6-12 RM zone using 1- to 2-min rest periods between sets at a moderate velocity. Higher volume, multiple-set programs are recommended for maximizing hypertrophy. Progression in power training entails two general loading strategies: 1) strength training and 2) use of light loads (0-60% of 1 RM for lower body exercises; 30-60% of 1 RM for upper body exercises) performed at a fast contraction velocity with 3-5 min of rest between sets for multiple sets per exercise (three to five sets). It is also recommended that emphasis be placed on multiple-joint exercises especially those involving the total body. For local muscular endurance training, it is recommended that light to moderate loads (40-60% of 1 RM) be performed for high repetitions (915) using short rest periods (G90 s). In the interpretation of this position stand as with prior ones, recommendations should be applied in context and should be contingent upon an individual's target goals, physical capacity, and training
There is not a strong research basis for current views of the importance of individual training variables in strength training protocol design. This study compared 1 day versus 3 days of resistance training per week in recreational weight trainers with the training volume held constant between the treatments. Subjects were randomly assigned to 1 of 2 groups: 1 day per week of 3 sets to failure (1DAY) or 3 days per week of 1 set to failure (3DAY). Relative intensity (percent of initial 1 repetition maximum [1RM]) was varied throughout the study in both groups by using a periodized repetition range of 3-10. Volume (repetitions x mass) did not differ (p <= 0.05) between the groups over the 12 weeks. The 1RMs of various upper-and lower-body exercises were assessed at baseline and at weeks 6 and 12. The 1RMs increased (p <= 0.05) significantly for the combined groups over time. The 1DAY group achieved ~62% of the 1RM increases observed in the 3DAY group in both upper-body and lower-body lifts. Larger increases in lean body mass were apparent in the 3DAY group. The findings suggest that a higher frequency of resistance training, even when volume is held constant, produces superior gains in 1RM. However, training only 1 day per week was an effective means of increasing strength, even in experienced recreational weight trainers. From a dose-response perspective, with the total volume of exercise held constant, spreading the training frequency to 3 doses per week produced superior results.
(C) 2000 National Strength and Conditioning Association
The authors assessed the diet and exercise habits and perceived barriers to following a healthy lifestyle of 471 college students. Sixty percent of the participants were female and 31% had BMIs > 25. Breakfast was the most commonly missed meal and 63% of students snacked one to two times per day. Fifty-eight percent of participants ate vegetables and 64% ate whole or canned fruit less than once per day. Men consumed more soda and alcohol and used higher fat dairy, ate more meat, and ate fewer vegetables and fruits than women. Over half of the subjects rated their diet as poor or fair with "lack of time" listed as the number one barrier to eating well. Men exercised more frequently and at greater intensity than women and were more confident with their body image. The most common barrier to exercise was "lack of time." The results of this study have implications for the design of general and specific diet and physical activity interventions among college students.
Magyari, PM and Churilla, JR. Association between lifting weights and metabolic syndrome among U.S. adults: 1999-2004 National Health and Nutrition Examination Survey. J Strength Cond Res 26(11): 3113-3117, 2012-The purpose of this cross-sectional study was to determine the proportion of U.S. adults who participate in the resistance exercise modality of lifting weights (LWs) by demographic characteristics and to investigate the impact of LWs on the prevalence and risk of metabolic syndrome (MetS) in a national representative sample of U.S. adults. The sample (n = 5,618) in this cross-sectional study included adults aged ≥20 years who participated in the 1999-2004 National Health and Nutrition Examination Survey. Approximately twice as many men (11.2%; 95% confidence interval [CI] 9.5, 13.1) reported LWs as women did (6.3%; 95% CI 5.2, 7.6) with non-Hispanic Whites (9.6%; 95% CI 8.1, 11.4) reporting the highest levels and Mexican Americans reporting the lowest levels (5.6%; 95% CI 4.4, 7.2) of engaging in LWs. Additionally, higher levels of socioeconomic status were associated with greater levels of self-reported LWs. MetS prevalence was found to be significantly lower among U.S. adults reporting LWs (24.6%; 95% CI 19.3, 30.9) compared with adults not reporting LWs (37.3%; 95% CI 35.5, 39.2) with associated risk reductions of 58% (p < 0.001) and 37% (p < 0.01) in the unadjusted model and model adjusted for demographic variables, respectively. These findings suggest that LWs may play a role in reducing the prevalence and risk of MetS among U.S. adults. Therefore, exercise professionals should strongly encourage the activity of LWs among adults of all ages to promote metabolic health and focus programs designed to increase the adoption of LWs among the subgroups who report the lowest levels of LWs.