Development of a Standard Push-up Scale for College-Aged Females.

The ACSM/CESP push-up test exemplifies the limiting nature of the gender binary in fitness. Males perform the standard push-up (from toes) while females perform the modified push-up (from knees), even if capable of multiple standard push-ups. Differences in upper body strength are used to justify the test protocol. Though the load difference between modified and standard positions is substantially less than the gender strength gap. Additionally, current fitness ratings are over 30 years old. The purpose of this study was to develop a new standard push-up rating scale for college-age females. Cis-female college students (n = 72) were recruited to perform maximal repetitions in the modified and standard positions. Health history and physical activity information was gathered prior to the test. Trained research assistants provided standardized warm-up, modelled correct form, and administered the tests. Order of the tests was randomized and there was at least 48 hours between test days. Mean push-ups in the standard position was 9 (8.87) and 17.5 (11.76) in the modified position. Participants who resistance train did significantly more repetitions of each. Linear regression was used to develop an equation to predict standard push-up repetitions from modified repetitions. The equation was applied to the current repetition ranges for each fitness category, and a new standard scale was developed. The new scale ratings are similar to the Revised Push-up but lower than the Fitnessgram® Healthy Zone. The modified or "girl" push-up contributes to gender stereotypes about muscular fitness. Providing females with the option to be graded on the standard push-up is a step to reducing gender bias in fitness. Future research is needed to validate this scale.

The myogenic repressor gene Holes in muscles is a direct transcriptional target of Twist and Tinman in the Drosophila embryonic mesoderm.

Understanding the regulatory circuitry controlling myogenesis is critical to understanding developmental mechanisms and developmentally-derived diseases. We analyzed the transcriptional regulation of a Drosophila myogenic repressor gene, Holes in muscles (Him). Previously, Him was shown to inhibit Myocyte enhancer factor-2 (MEF2) activity, and is expressed in myoblasts but not differentiating myotubes. We demonstrate that different phases of Him embryonic expression arises through the actions of different enhancers, and we characterize the enhancer required for its early mesoderm expression. This Him early mesoderm enhancer contains two conserved binding sites for the basic helix-loop-helix regulator Twist, and one binding site for the NK homeodomain protein Tinman. The sites for both proteins are required for enhancer activity in early embryos. Twist and Tinman activate the enhancer in tissue culture assays, and ectopic expression of either factor is sufficient to direct ectopic expression of a Him-lacZ reporter, or of the endogenous Him gene. Moreover, sustained expression of twist in the mesoderm up-regulates mesodermal Him expression in late embryos. Our findings provide a model to define mechanistically how Twist can both promotes myogenesis through direct activation of Mef2, and can place a brake on myogenesis, through direct activation of Him.

A hybrid online intervention for reducing sedentary behavior in obese women.

Sedentary behavior (SB) has emerged as an independent risk factor for cardiovascular disease and type 2 diabetes. While exercise is known to reduce these risks, reducing SB through increases in non-structured PA and breaks from sitting may appeal to obese women who have lower self-efficacy for PA. This study examined effects of a combined face-to-face and online intervention to reduce SB in overweight and obese women. A two-group quasi-experimental study was used with measures taken pre and post. Female volunteers (M age = 58.5, SD = 12.5 years) were enrolled in the intervention (n = 40) or waitlisted (n = 24). The intervention, based on the Social Cognitive Theory, combined group sessions with email messages over 6 weeks. Individualized feedback to support mastery and peer models of active behaviors were included in the emails. Participants self-monitored PA with a pedometer. Baseline and post measures of PA and SB were assessed by accelerometer and self-report. Standard measures of height, weight, and waist circumference were conducted. Repeated measures ANOVA was used for analyses. Self-reported SB and light PA in the intervention group (I) changed significantly over time [SB, F(1, 2) = 3.81, p = 0.03, light PA, F(1, 2) = 3.39, p = 0.04]. Significant Group × Time interactions were found for light PA, F(1, 63) = 5.22, p = 0.03, moderate PA, F(1, 63) = 3.90, p = 0.05, and for waist circumference, F(1, 63) = 16.0, p = 0.001. The intervention group decreased significantly while the comparison group was unchanged. Hybrid computer interventions to reduce SB may provide a non-exercise alternative for increasing daily PA and potentially reduce waist circumference, a risk factor for type 2 diabetes. Consumer-grade accelerometers may aide improvements to PA and SB and should be tested as part of future interventions.

Physical activity and quality of life.

Physical activity (PA) professionals and participants recognize enhanced quality of life (QoL) as a benefit of and motivator for PA. However, QoL measures are often problematic and rarely consider the participants'perspective. This paper focuses on recent findings from a larger project on the role of QoL in PA and health promotion. More specifically, we focus on the views of participants and potential participants to better understand the relationship of PA and QoL. In earlier stages of the project we began with a conceptual model of QoL and developed a survey. We now focus on participants' views and ask two questions: 1) what is QoL? and 2) how does PA relate to QoL? We first asked those questions of a large sample of university students and community participants as open-ended survey items, and then asked focus groups of community participants. Overall, participants' responses reflected the multidimensional, integrative QoL model, but the responses and patterns provided information that may not be picked up with typical survey measures. Findings suggest that PA contributes to multiple aspects of QoL, that social and emotional benefits are primary motivators and outcomes for participants, and that the meaning of QoL and PA benefits is subjective and contextualized, varying across individuals and settings. Programs that directly target and highlight the multiple dimensions and integrative QoL, while considering the individual participants and contexts, may enhance both PA motivation and participants' health and QoL.

Comparison of the effects of body-weight-supported treadmill training and tilt-table standing on spasticity in individuals with chronic spinal cord injury.

OBJECTIVE: Determine the effects of body-weight-supported treadmill training (BWSTT) and tilt-table standing (TTS) on clinically assessed and self-reported spasticity, motor neuron excitability, and related constructs in individuals with chronic spinal cord injury (SCI). DESIGN: Random cross-over. METHODS: Seven individuals with chronic SCI and spasticity performed thrice-weekly BWSTT for 4 weeks and thrice-weekly TTS for 4 weeks, separated by a 4-week wash-out. Clinical (Modified Ashworth Scale, Spinal Cord Assessment Tool for Spinal reflexes) and self-report (Spinal Cord Injury Spasticity Evaluation Tool, Penn Spasm Frequency Scale) assessments of spasticity, quality of life (Quality of Life Index Spinal Cord Injury Version - III), functional mobility (FIM Motor Subscale), plus soleus H-reflex were measured at baseline, after the first training session and within 2 days of completing each training condition. RESULTS: In comparison with TTS, a single session of BWSTT had greater beneficial effects for muscle tone (effect size (ES) = 0.69), flexor spasms (ES = 0.57), and the H/M ratio (ES = 0.50). Similarly, flexor spasms (ES = 0.79), clonus (ES = 0.66), and self-reported mobility (ES = 1.27) tended to benefit more from 4 weeks of BWSTT than of TTS. Participation in BWSTT also appeared to be favorable for quality of life (ES = 0.50). In contrast, extensor spasms were reduced to a greater degree with TTS (ES = 0.68 for single session; ES = 1.32 after 4 weeks). CONCLUSION: While both BWSTT and TTS may provide specific benefits with respect to spasticity characteristics, data from this pilot study suggest that BWSTT may result in a broader range of positive outcomes.

A molecular mechanism of temperature sensitivity for mutations affecting the Drosophila muscle regulator Myocyte enhancer factor-2.

Temperature-sensitive (TS) mutations are a useful tool for elucidating gene function where a gene of interest is essential at multiple stages of development. However, the molecular mechanisms behind TS alleles vary. TS mutations of the myogenic regulator Myocyte enhancer factor-2 (MEF2) in Drosophila arise in the heteroallelic combination Mef2(30-5)/Mef2(44-5). We show that the 30-5 mutation affects the N-terminal MADS domain, causing impaired DNA binding ability and failure of homozygous mutants to survive to adulthood. The 44-5 mutation deletes a downstream splice acceptor site and results in a truncated protein that is unable to activate MEF2 targets. 44-5 homozygotes consequently show severely impaired myogenesis and die as embryos. We propose that in heteroallelic mutants at the permissive temperature, 30-5/44-5 heterodimers form and have a sufficiently stable interaction with DNA to activate myogenic gene expression; at the restrictive temperature, 44-5 homodimers displace 30-5/44-5 heterodimers from target genes, thus acting in a dominant-negative manner. To test this, we show that 30-5/44-5 heterodimers can form, and we study additional Mef2 alleles for complementation with the 30-5 allele. An allele affecting the DNA binding domain fails to complement 30-5, whereas two alleles affecting downstream residues show temperature-dependent complementation. Thus, by combining one MEF2 isoform having weakened DNA binding ability with a second truncated MEF2 mutant that has lost its activation ability, a TS form of intragenic complementation can be generated. These findings will provide new insight and guidance into the functions of dimeric proteins and how they might be engineered to generate TS combinations.

Effects of short-term training on heart rate dynamics in individuals with spinal cord injury.

Increased risk of cardiovascular diseases and autonomic dysregulation are common health concerns in individuals with spinal cord injury (SCI). Two therapies that may help improve cardiovascular control are body-weight supported treadmill training (BWSTT) and head-up tilt training (HUTT). The purpose of this study was to examine the effects of short-term BWSTT and HUTT on cardiac autonomic function. Seven participants (6 male, 37.1+/-7.7 years) with SCI (C5-T10, ASIA A-C; 5.0+/-4.4 years post-injury) completed the study protocol. In this randomized cross-over design, participants were required to complete 4 weeks of thrice-weekly BWSTT and HUTT (i.e. 12 sessions each), separated by a 4 week detraining period. Cardiac autonomic function was assessed at rest, before and after, each 4 week training period using linear and non-linear measures (sample entropy and detrended fluctuation analysis (alpha(1))) of heart rate dynamics. Participants completed equivalent amounts of time performing BWSTT and HUTT (453.7+/-27.3 min vs. 471.6+/-19.7 min, p=0.24). There were no significant differences in linear heart rate variability following BWSTT or HUTT (p>0.05). In contrast, there was a significant change in sample entropy following BWSTT (1.05+/-0.14 to 1.42+/-0.12, p<0.05). Due to the bi-directional pattern of alpha(1) values, distance scores were calculated (|1-alpha(1)|) and demonstrated a significant reduction following BWSTT (0.54+/-0.06 to 0.26+/-0.05, p=0.001). In conclusion, 4 weeks of BWSTT but not HUTT training are sufficient to increase sample entropy and reduce the fractal scaling distance score in participants with SCI.

The spinal cord injury spasticity evaluation tool: development and evaluation.

OBJECTIVE: To develop and assess the reliability and validity of a new scale designed to measure the impact of spasticity on daily life in people with spinal cord injury (SCI). DESIGN: Scale development and assessment. SETTING: General community. PARTICIPANTS: Community-dwelling persons with chronic SCI and spasticity participated in study 1 (n=9), study 2 (n=19), and study 3 (n=61). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Study 1: participant definitions of spasticity and list of scale items. Study 2: scale refinement, face validity, and time to complete. Study 3: internal consistency, test-retest reliability, and construct validity. RESULTS: The Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) is a 7-day recall self-report questionnaire that takes into account both the problematic and useful effects of spasticity on daily life in people with SCI. The scale exhibited good face validity and required 6.8+/-2.6 minutes to complete. The internal consistency (alpha) and intraclass correlation coefficient of the SCI-SET were .90 and .91, respectively. Construct validity was supported by correlations (r range, -.48 to .68; P<.01) between SCI-SET scores and theoretically meaningful constructs. CONCLUSIONS: The SCI-SET fills a need for a reliable and valid self-report measure of the impact of spasticity on daily life in people with SCI, taking into account both the problematic and useful effects of spasticity.

The effect of body weight-supported treadmill training on muscle morphology in an individual with chronic, motor-complete spinal cord injury: A case study.

OBJECTIVE: The purpose of this pilot study was to examine the effects of 4 months of thrice-weekly body weight-supported treadmill training (BWSTT) on skeletal muscle morphology in a woman (age 27 y) with chronic, motor-complete (ASIA B) spinal cord injury (SCI). METHODS: The participant performed passive thrice-weekly BWSTT for 4 months (48 total sessions) with manual assistance from therapists. Muscle biopsies of the vastus lateralis were taken prior to the beginning of the training program as well as following the completion of 4 months of training. Histochemical analysis was utilized to evaluate changes in muscle fiber size and type following training. RESULTS: At baseline, vastus lateralis muscle biopsies showed evidence of fiber atrophy and fiber type redistribution typical of persons with SCI, with mean fiber areas (and % distributions) of type I, type IIa and type IIx fibers being 3474 microm2 (1.3%), 3146 microm2 (30.8%) and 1284 microm2 (68.0%), respectively. Following training, there were increases in treadmill walking speed (pre: 1.0km/h; post: 2.5km/h) and distance walked/session (pre: 500m; post: 1875m). Vastus lateralis mean fiber area increased by 27.1% and type I fiber % distribution increased to 24.6%, whereas type IIa and type IIx fiber % distributions both decreased following training. CONCLUSION: These data indicate that 4 months of thrice-weekly BWSTT improved muscle morphology in an individual with chronic, motor-complete SCI.