IJES Self-Study on Participants' Sex in Exercise Science: Sex-Data Gap and Corresponding Author Survey.

A sex-data gap exists between females and males within the sport and exercise science literature, and implications are far-reaching. The purpose of this work was to (a) heed recent calls and scrutinize data from within IJES to address the gap and (b) gain insight on self-identified sex of IJES corresponding authors. The present self-study included all published manuscripts from 2008 through 2021. A total of 851 publications were included, and 806 (94.7%) reported data on participant sex. There was a difference between publications that included only females (n = 132) versus only males (n = 215), and three publications reported data on sex according to non-binary identifications (0.4%). There was an overall difference between the number of female (n = 54,153; 35.9%) and male (n = 96,890; 64.1%) participants. To gain insight on self-identified sex of corresponding authors, we performed an IRB-approved research study. Among 761 unique corresponding authors, 168 individuals provided 157 usable responses-58 biological females (36.9%) and 99 biological males (63.1%). We fully support the prerogative of researchers to ethically conduct investigations and encourage open-mindedness and inclusion in future research. With data revealing an approximate one-third female (36%) and two-thirds male (64%) composition, and corresponding author feedback on self-identified sex being similar (36.9% and 63.1%, respectively), we propose a new concept that should be analyzed: is the sex-data gap representative of the composition of the field? We are not excusing the sex-data gap issue as if it cannot be addressed, and we urge others to join us in researching this line of inquiry.

Efficacy of Army Combat Fitness Test 12-Week Virtual Exercise Program.

INTRODUCTION: The Army Combat Fitness Test (ACFT) is the fitness assessment used by the Army launched in April of 2022. The ACFT consists of six physically demanding motor movements that parallel to the stressors experienced by the modern-day combat soldier. The aim of this study is to determine the efficacy of a 12-week virtual exercise program on the individual and their overall ACFT scores. MATERIALS AND METHODS: Thirteen soldiers from the Army National Guard (age = 29.8 ± 6.2 years; height = 175.7 ± 6.1 cm; service experience ≥ 18 months to 18 years) volunteered to complete three sessions. In session 1, baseline height, body mass, body composition, and ACFT scores were collected. Session 2 consisted of a suspension trainer (ST) tutorial in which all participants familiarized themselves with the set-up and utilization of the suspension training tool kit. Upon completion of session 2, a TRX Elite ACFT Kit containing one suspension trainer, four resistance bands, and the 12-week virtual exercise training program available via iphone operating system and Android were given to all participants. In session 3, post-assessments of body mass, body composition, and ACFT scores were collected. Data were statistically analyzed using a paired-sample t-test with a Bonferroni correction (P < .00065) to adjust for multiple comparisons. RESULTS: There were no significant changes in mean body mass (83.8 ± 16.5 kg vs. 83.9 ± 16.6 kg; P = .752); however, there was a significant reduction in mean percentage body fat (19.5 ± 6.4% vs. 18.3 ± 6.5%; P < .0001). Mean scores from four of the six individual ACFT assessments, specifically, deadlift, standing power throw, hand-release push-ups, and sprint-drag-carry, displayed improvements, but did not attain statistical significance. The overall mean ACFT scores displayed significant improvements (319.4 ± 39.9 vs. 390.4 ± 68.5; P < .0001). CONCLUSIONS: The TRX Elite ACFT Kit which includes one suspension trainer, four varying resistance bands, and on-demand access to a stepwise 12-week virtual exercise program was deemed effective by increasing the overall mean ACFT scores among participants. From a practitioner's perspective, the TRX Elite ACFT Kit should be widely distributed to all Army units and recruiting commands to provide vital assistance for recruits and soldiers to train and prepare for the ACFT. Moreover, given the ease and portability of the TRX Elite ACFT Kit, recruits and soldiers will be able to effectively train anytime, anywhere.

Efficacy of a 6-Week Suspension Training Exercise Program on Fitness Components in Older Adults.

The purpose of this study was to determine the efficacy of a 6-week suspension training exercise program on fitness components in older adults. Eleven participants (age = 80 ± 5 yrs) completed a 6-week suspension training exercise program. Pre- and post-fitness assessments comprised of body composition, handgrip dynamometer, functional reach, and balance. The 6-week suspension training intervention required individuals to perform suspension training exercises for fifty minutes, twice per week. A paired sample t-test was used to determine differences from pre-and post-assessments. An improvement was observed in functional reach (57.2 ± 6.4 cm vs 68.6 ± 4.3 cm; p = 0.02) and overall balance score (67.5 ± 2.4 vs 72.2 ± 2.2; p = 0.02). A 6-week suspension training exercise program can be adequate to enhance core stability and overall balance amongst older adults. This paradigm should be explored further to determine the effects on fall-risk and fall prevention.

Evaluating the Intra-Rater and Inter-Rater Reliability of Fixed Tension Scale Instrumentation for Determining Isometric Neck Strength.

PURPOSE: The purpose of this study was to evaluate the reliability of a fixed tension scale instrumentation, comparing the intra-rater and inter-rater reliability between seating and standing measurement techniques. Instrumentation developed from this study will be utilized to assess isometric neck strength in future studies comparing neck strengthening protocols. METHODS: Isometric neck strength for eight movements (cervical/capital flexion, cervical/capital extension, left/right lateral flexion, left/right cervical rotation) as well as anthropometric measurements were evaluated for thirty-one participants through the use of a novel neck strength assessment protocol. RESULTS: The fixed tension scale instrumentation and methods used in this study demonstrated good to excellent intra-rater reliability (ICC range from 0.78 to 0.97) as well as moderate to excellent inter-rater reliability (ICC range from 0.73 to 0.91) for both measurement techniques. PRACTICAL APPLICATIONS: This study will provide foundational knowledge for the reliable assessment of neck strength. Additionally, the findings will provide a cost-effective, portable, and reliable instrument for measuring isometric neck strength. CONCLUSIONS: Seated and standing measurement techniques demonstrated similar intra and inter-rater reliability. Inter-rater reliability tended to be lower with motions (capital flexion and extension) that required the participants to face directly towards or away from the instrumentation. This could be due to participant positioning or unfamiliarity with those specific movements. The assessment protocol utilized in this study demonstrated comparable inter-rater reliability to another cost-effective method for evaluating isometric neck strength.

Falls in young adults: The effect of sex, physical activity, and prescription medications.

Falls are a major public health issue not only for older adults but also young adults, with fall-related injuries occurring more frequently in adult females than males. However, the sex differences in the frequency and circumstances of falls in young adults are understudied. This research quantified the frequency and circumstances of falls as a function of sex, physical activity, and prescription medications in young adults. For 16 weeks, young adult participants (N = 325; 89 males; 19.9±1.1 years) responded to a daily email asking if they had slipped, tripped, or fallen in the past 24 hours. Falls and fall-related injuries were not uncommon in young adults: 48% fell at least once, 25% fell more than once, and 10% reported an injury. The most common activities at the time of the fall for females were walking (44%) and sports (33%), and for males, sports (49%) and walking (37%). A zero-inflated Poisson model revealed that higher number of falls were associated with the following: higher levels of physical activity (p = 0.025), higher numbers of medications (p<0.0001), and being male (p = 0.008). Regarding circumstances of falling, females were more likely to be talking to a friend at the time of the fall (OR (95% CI): 0.35 (0.14-0.73); p = 0.01). For slips and trips without a fall, males and females reported the same number of slips (OR (95% CI): 0.885 (0.638-1.227) p = 0.46), but females reported more trips (OR (95% CI): 0.45 (0.30-0.67); p<0.01). Only females reported serious injuries such as concussion and fracture. In conclusion, the rate of falls in young adults was affected by physical activity levels, number of medications, and sex. Quantifying and understanding these differences leads to increased knowledge of falls across the lifespan and is instrumental in developing interventions to prevent falls.

Failures in adaptive locomotion: trial-and-error exploration to determine adequate foot elevation over obstacles.

Lifting the limb sufficiently to clear an obstacle seems like a straightforward task, yet trips are a common cause of falls across all ages. Examination of obstacle contacts in the lab revealed a progressive decrease in foot elevation with repeated exposures, ultimately resulting in failure (Heijnen et al. Exp Brain Res 23:219-231, 2012). The purpose of this study was to determine if the progressive decrease in foot elevation continued when knowledge of obstacle contact was removed. Twenty-one young adults (mean 20.0 ± 1.0 years; 8 males) crossed a 20 cm obstacle in a 12 m walkway for 150 trials. The obstacle was covertly lowered between the lead and trail limb crossing of the obstacle, which eliminated obstacle contact with the trail limb if the limb was too low. The average failure rate was 8%, substantially higher than the 1-2% observed for stationary, visible obstacles. Therefore, tactile information from obstacle contact was instrumental for guiding the trail limb; visual information and joint angle information were insufficient for most participants. Foot elevation change over successive trials varied across participants, and was categorized as (1) asymptotic decrease (N = 11, 52%), with foot elevation converging to obstacle height, (2) linear decrease (N = 7, 33%), and (3) stable (N = 3, 14%). The asymptotic and stable groups appeared to have reasonable knowledge of obstacle height; the linear group did not. The asymptotic behavior is consistent with participants exploring the region above the obstacle through trial-and-error to determine appropriate foot elevation.

Memory-guided obstacle crossing: more failures were observed for the trail limb versus lead limb.

During adaptive locomotion, vision is used to guide the lead limb; however, the individual must rely on knowledge of obstacle height and position, termed obstacle memory, to guide the trail limb. Previous research has demonstrated that visual sampling of the obstacle during approach was adequate to provide obstacle height information, but online visual update of distance to the obstacle was required to plan and implement appropriate foot placement. Our purpose was to determine whether obstacle height memory, coupled with a visible obstacle position cue, could successfully guide the foot during obstacle crossing. Subjects first stepped over an obstacle for 25 trials; then, the obstacle was removed, but its position was marked with high-contrast tape; subjects were instructed to step over the obstacle as if it was still there (termed "virtual obstacle") for 25 trials. No changes in foot placement were observed; therefore, the position cue provided salient online information to guide foot placement. Average failure rates (subject would have contacted the virtual obstacle if it was present) were 9 and 47 % (lead and trail limb, respectively). Therefore, action was impaired for both limbs when guided by obstacle height memory, but action was impaired to a greater extent for the trail limb. Therefore, viewing the obstacle during approach appears to facilitate the memory needed to guide obstacle crossing, particularly for the trail limb. This is likely because the lead limb is visible in the peripheral visual field during crossing, but the trail limb is not.

Factors leading to obstacle contact during adaptive locomotion.

During everyday life, healthy adults occasionally trip over an obstacle that they knew was there. These 'spontaneous' trips can provide insight into the circumstances leading to trips and falls. The goal of this study was to describe the errors in foot placement and/or foot elevation that resulted in a spontaneous contact with a fixed, visible obstacle in young, healthy adults. Fifteen subjects stepped over an obstacle (height set to 25 % leg length) placed in the middle of an 8 m walkway, up to 300 times. Three subjects never contacted the obstacle and 12 subjects contacted the obstacle 1-4 times, totaling 24 contacts in 3,843 trials (0.6 %). Most of the contacts (92 %) were with the trail limb. Minimum foot clearance of the trail limb (trail MFC) decreased linearly (average slope of -1 mm/trial) with repeated trials. The majority of subjects (70 %) continued the linear decrease of trail MFC until they contacted the obstacle. The remaining contacts resulted from an apparent misjudgment of foot placement and/or foot elevation. Following contact, trail MFC increased 75 % in the subsequent trials and remained elevated at least up to 30 trials post-contact, but the trajectory of the unperturbed lead limb did not change, further supporting the idea of independent control for the lead and trail limbs during obstacle crossing. Possible causes of the progressive decrease in trail MFC until obstacle contact are considered.

Interpolation techniques to reduce error in measurement of toe clearance during obstacle avoidance.

Foot and toe clearance (TC) are used regularly to describe locomotor control for both clinical and basic research. However, accuracy of TC during obstacle crossing can be compromised by typical sample frequencies, which do not capture the frame when the foot is over the obstacle due to high limb velocities. The purpose of this study was to decrease the error of TC measures by increasing the spatial resolution of the toe trajectory with interpolation. Five young subjects stepped over an obstacle in the middle of an 8 m walkway. Position data were captured at 600 Hz as a gold standard signal (GS-600-Hz). The GS-600-Hz signal was downsampled to 60 Hz (DS-60-Hz). The DS-60-Hz was then interpolated by either upsampling or an algorithm. Error was calculated as the absolute difference in TC between GS-600-Hz and each of the remaining signals, for both the leading limb and the trailing limb. All interpolation methods reduced the TC error to a similar extent. Interpolation reduced the median error of trail TC from 5.4 to 1.1 mm; the maximum error was reduced from 23.4 to 4.2 mm (16.6-3.8%). The median lead TC error improved from 1.6 to 0.5 mm, and the maximum error improved from 9.1 to 1.8 mm (5.3-0.9%). Therefore, interpolating a 60 Hz signal is a valid technique to decrease the error of TC during obstacle crossing.