Female Runners Research Articles

Recovery of heart rate and heartrate variability after a maximal cardiopulmonary exercise test in novice female runners.

Previous studies have shown delayed cardiac vagal reactivation after high-intensity endurance exercise when estimated with heartrate variability (HRV). However, the recovery dynamics of RR intervals (RRI) and HRV after a maximal incremental exercise test have been studied less in non-athletic population and especially in females. The main aim of the study was to examine the recovery dynamics of RRI and HRV immediately after a maximal cardiopulmonary exercise test (CPET) in adult females. Twenty-eight healthy, novice recreational female runners (33.7 ± 4.2years) were selected to participate in this study from a larger group of participants (Run RCT). RRIs were collected continuously during a controlled rest, a CPET on a treadmill and a 15-min controlled, passive recovery. Minute-by-minute recovery dynamics were analyzed. The dynamic phase of RRI and heart rate recovery (HRR) (from 192.2 ± 9.9 to 111.4 ± 2.4, P < 0.001) occurred during the first 4.5min with HRR of 36 ± 10 beats during the first minute of the recovery. Resting heart rate was negatively associated (r = - 0.53, P = 0.016) with HRR during the recovery. No recovery of root mean square of successive RRIs (RMSSD) was detected during the 15-min recovery. RMSSD was 15.0 ± 9.2% of resting values at the end of the recovery. No recovery of vagal-derived HRV was detected immediately after a CPET in novice recreational female runners despite marked changes in sympathovagal balance, detected by rapid recovery of RRI during the first 5min after exercise cessation.

Cross-sectional size, shape, and estimated strength of the tibia, fibula and second metatarsal in female collegiate-level cross-country runners and soccer players

Bone stress injuries (BSIs) frequently occur in the leg and foot long bones of female distance runners. A potential means of preventing BSIs is to participate in multidirectional sports when younger to build a more robust skeleton. The current cross-sectional study compared differences in tibia, fibula, and second metatarsal diaphysis size, shape, and strength between female collegiate-level athletes specialized in cross-country running (RUN, n = 16) and soccer (SOC, n = 16). Assessments were performed using high-resolution peripheral quantitative computed tomography and outcomes corrected for measures at the radius diaphysis to control for selection bias and systemic differences between groups. The tibia in SOC had a 7.5 % larger total area than RUN, with a 29.4 % greater minimum second moment of area (IMIN) and 8.2 % greater estimated failure load (all p ≤ 0.02). Tibial values in SOC exceeded reference data indicating positive adaptation. In contrast, values in RUN were similar to reference data suggesting running induced limited tibial adaptation. RUN did have a larger ratio between their maximum second moment of area (IMAX) and IMIN than both SOC and reference values. This suggests the unidirectional loading associated with running altered tibial shape with material distributed more in the anteroposterior (IMAX) direction as opposed to the mediolateral (IMIN) direction. Comparatively, SOC had a similar IMAX/IMIN ratio to reference data suggesting the larger tibia in SOC resulted from multiplane adaptation. In addition to enhanced size and strength of their tibia, SOC had enhanced structure and strength of their fibula and second metatarsal. At both sites, polar moment of inertia was approximately 25 % larger in SOC compared to RUN (all p = 0.03). These data support calls for young female athletes to delay specialization in running and participate in multidirectional sports, like soccer, to build a more robust skeleton that is potentially more protected against BSIs.

Advanced footwear technology and its impacts on running mechanics, running economy and perception of male and female recreational runners

Studies on advanced footwear technology (AFT) often investigate potential performance benefits for constraint populations, and high running speeds. This research compared running biomechanics, running economy and perception between males and females, when wearing three different AFT conditions at recreational running speeds. An innovation shoe sample (IM) at confirmation stage in the product creation process was compared to two commercial running shoes (MM, MF). Gender and shoe variable means were compared for main and interaction effects (p < 0.05) by a mixed 2 × 3 repeated measures analysis of variance (RM ANOVA), and effect size estimation. A main effect was seen for shoe condition, both the IM and MF showed higher vertical loading rates than MM, and higher peak vertical force 1. IM had less frontal plane rearfoot motion than both the MM and MF. At the MTPJ, IM had lower maximum dorsiflexion angle, dorsiflexion velocity leading to lower negative power and negative work than both the MM and MF. IM and MF showed significantly lower oxygen consumption than the MM. Perception measurements showed IM and MF to be significantly softer, responsive and had better propulsion than the MM. A main effect was seen for gender, females exhibited higher vertical loading rates, reduced frontal plane ankle motion and lower MTPJ motion, and lower oxygen consumption compared to males. There was no gender effect for perception. Despite biomechanical differences, both IM and MF showed improved performance compared to the MM. Males and females exhibit different biomechanics when wearing AFT, however this did not lead to differences in subjective perception. It is concluded that the specific AFT applied for IM samples in this research functions for both groups largely similarly.

Current iliotibial band syndrome alters patterns of running coordination in male and female runners, but not their levels of coordination variability

ABSTRACT The aim of the present study was to compare the coordination patterns and levels of coordination variability of healthy and injured runners with iliotibial band syndrome (ITBS). Sixty runners divided into four groups (15 healthy males, 15 healthy females, 15 males with ITBS and 15 females with ITBS) ran at a steady and freely chosen pace on an over-ground track, and their coordination patterns of the lower limbs were calculated during 10 running stances using the vector coding technique. Both male and female runners with ITBS showed a greater dominance of the pelvis segment and the anti—phase patterns in the frontal plane thigh—pelvis coupling (p = 0.001, η 2 = 0.36). In addition, injured female runners showed a greater hip adduction dominance, whereas injured males presented a greater anti—phase pattern in the transverse plane—frontal plane hip coupling (p = 0.003, η2 = 0.08). The levels of coordination variability during running stance did not change between ITBS injured and healthy runners in any of the couplings. Currently injured runners with ITBS appeared to present altered coordination patterns on the hip couplings that were partly dependent on gender but did not lead to changes in the coordination variability levels.

The influence of longitudinal bending stiffness on running economy and biomechanics in male and female runners

The purpose of this study was to evaluate the influence of different longitudinal bending stiffnesses (LBS) on running economy and lower extremity joint biomechanics in male and female runners. Thirty participants (15 F;15M) performed a treadmill protocol of five-minute randomised aerobic runs with four different footwear conditions varying in LBS: 16.1 N/mm; 32.7 N/mm; 46.1 N/mm; 90.1 N/mm. Biomechanical data was collected at the metatarsophalangeal (MTP) and ankle joints. Running economy was quantified via oxygen consumption data. Oxygen consumption observed no significant differences between footwear conditions (p = 0.960) or significant interaction between footwear and sex (p = 0.126). Stance time observed a significant difference between footwear conditions (p < 0.001), and a significant interaction of footwear and sex (p = 0.008), increasing in females as stiffness increased. At the MTP joint, a shoe effect was present for peak bending angle (p < 0.001), peak extension (p = 0.040) and flexion (p < 0.001) angular velocity, and energy generated at the joint (p = 0.010). There was also an interaction effect of peak MTP extension angular velocity (p = 0.044), with females slightly decreasing as stiffness increased, with no reaction from males. At the ankle joint, a shoe effect was present for peak dorsiflexion (p < 0.001) and plantarflexion (p < 0.001) angular velocity, peak negative power (p < 0.001) and energy absorbed at the joint (p < 0.001). Comparing the interaction between shoe condition and male/female runners, male and female runners reacted similarly to the increased LBS with no effect on running economy and subtle changes in the stance time and MTP angular velocity for female runners. While further research is needed in this area investigating aspects related to sex-specific optimal stiffness element location and geometry, it does not appear that the stiffness magnitude has a sex dependence.

Effects of prosthetic stiffness and added mass on metabolic power and asymmetry in female runners with a leg amputation.

Similar to nonamputees, female athletes with unilateral transtibial amputation (TTA) using running-specific leg prostheses (RSPs) may have worse running economy and higher rates of running-related injury than male athletes. Optimizing RSP configuration for female athletes could improve running economy and minimize biomechanical asymmetry, which has been associated with running-related injury. Nine females with a TTA ran at 2.5 m/s while we measured metabolic rates and ground reaction forces. Subjects used an RSP with a manufacturer-recommended stiffness category, one category less stiff and two categories less stiff than recommended. Use of an RSP two categories less stiff resulted in 3.0% lower net metabolic power (P = 0.04), 7.8% lower affected leg stiffness (P = 6.01 × 10-4), increased contact time asymmetry (P = 0.04), and decreased stance average vertical ground reaction force asymmetry (P = 0.04) compared with a recommended stiffness category RSP. Lower RSP stiffness (kN/m) values were associated with lower net metabolic power (P = 0.02), lower affected leg stiffness (P = 1.36 × 10-4), longer affected leg contact time (P = 1.46 × 10-4), and similar affected leg peak and stance-average vertical ground reaction force compared with higher RSP stiffness values. Subjects then used the RSP stiffness category that elicited the lowest net metabolic power with 100 g, 200 g, and 300 g added distally. We found no significant effects of added mass on net metabolic power, biomechanics, or asymmetry. These results suggest that female runners with a TTA could decrease metabolic power during running while minimizing biomechanical asymmetries, which have been associated with running-related injury, by using an RSP two categories less stiff than manufacturer recommended.NEW & NOTEWORTHY Females with unilateral transtibial amputation can improve running performance through reductions in net metabolic power by using a running-specific prosthesis (RSP) that is less stiff than manufacturer-recommended. Lower RSP stiffness values are associated with greater leg stiffness and contact time asymmetry, and lower stance-average vertical ground reaction force asymmetry. However, we found that adding mass to the RSP did not affect net metabolic power and stance-phase biomechanical asymmetries during running.

Associations between running mechanics, functional lower extremity strength, and stress urinary incontinence in parous female runners.

Women with stress urinary incontinence (SUI) may have altered running mechanics and reduced hip muscle strength compared to women without SUI. Little research has examined running metrics and functional lower extremity strength of parous runners. To determine if stress urinary incontinence (SUI) severity correlates with running metrics and lower extremity muscle strength among parous women. Cross-sectional observational study of 22 parous participants (mean age 39.8 years, with a mean of 3.4 pregnancies and 8.1 years interval since last delivery). Participants completed the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI), Urinary Distress Inventory (UDI) 6, Colorectal-Anal Distress (CRAD) Inventory 8, and Pelvic Organ Prolapse Distress Inventory (POPDI) 6, Questionnaire for Urinary Incontinence Diagnosis (QUID), and provided demographic, relevant running, and obstetric/gynecologic history information. After a brief warm-up, participants completed 30-second single leg sit to stand tests bilaterally and a standardized 10-minute treadmill run with pod cadence assessment. Pearson-product moment correlation coefficients were calculated (alpha = 0.05). Prolonged ground contact times were associated with higher ICIQ-UI SF (r = 0.523, p = 0.015), POPDI-6 (r = 0.694, p < 0.001), and UDI-6 scores (r = 0.577, p = 0.006), while lower cadences were associated with higher POPDI-6 (r = -0.550, p = 0.010) and UDI-6 scores (r = -0.444, p=0.044). Parous female runners with more severe SUI and prolapse symptoms demonstrate altered running mechanics characterized by prolonged ground contact times and slower cadences.

Analysis of Kinematic Variables According to Menstrual Cycle Phase and Running Intensity: Implications for Training Female Athletes

Depending on the phase of the menstrual cycle, different values of running kinematic variables can be obtained. The aim of this study is to analyze whether there are changes in the kinematic variables in running throughout the menstrual cycle and to relate them to running performance and injury prevention. Eight regular female runners and triathletes performed a maximal treadmill test, as well as a submaximal test (6′ stages at 50%, 60% and 80% of maximal aerobic speed) in each of the phases of the menstrual cycle: menstruation phase (day 2.4 ± 0.7), follicular phase (day 10.4 ± 2.2) and luteal phase (day 21.8 ± 2.1). Running dynamics were measured using RunScribe. For parametric data, a general linear model of repeated measures was applied, with two intrasubject independent variables, menstrual cycle phases (with three levels: Menstruation, Follicular, and Luteal) and running intensity (with four levels relative to the maximum speed reached in the test: 100%, 80%, 60%, and 50%). For variables with non-normal distributions, Friedman tests were performed with Wilcoxon post-tests adjusted for significance according to Bonferroni. The maximum stance velocity from foot strike to the point of maximum pronation (°/s) was higher in the menstruation phase than in the follicular and luteal phases (p = 0.008), the step rate (s/min) was higher in the follicular phase than in the menstruation and luteal phases (p = 0.049), the vertical velocity (m/s) was lower in the follicular phase than in the menstruation (p = 0.004) and luteal phases (p = 0.003), and the contact time (ms) was lower in the luteal phase than in the menstruation and follicular phases. These results suggest that training at high intensities could be a factor in greater risk of injury in female athletes, especially in the menstruation phase, finding in the luteal phase and at an intensity of 80% a greater efficiency in the running.

Repeated Bout Effect of Downhill Running on Physiological Markers of Effort and Post Exercise Perception of Soreness in Trained Female Distance Runners.

This study examined the effect of repeated bouts of level and downhill running on physiological markers of effort and exercise-induced muscle soreness in trained female distance runners. Ten participants (Age: 24.4 ± 2.0 years; V̇O2peak: 52.9 ± 1.1 mL·kg-1·min-1), naïve to downhill running, completed six alternate 5 min trials of level and downhill running (-15%) at a 70% velocity at V̇O2peak on two occasions, three weeks apart. Perceived muscle soreness was measured upon completion and in the 72 h post exercise. V̇O2, Heart Rate (HR), Blood Lactate (BLa), and Respiratory Exchange Ratio (RER) were lower running downhill (p < 0.016, ηp2 > 0.541). For the first downhill run, Rating of Perceived Exertion (RPE) was higher compared to that for level running (p = 0.051; d = 0.447), but for the remaining trials, RPE was lower when running downhill (p < 0.004; d > 0.745). V̇O2, HR, and RER were not different in the second bout (p > 0.070, ηp2 < 0.318); however, V̇O2 was lower in each downhill trial (Δ = 1.6-2.2 mL·kg-1·min-1; d = 0.382-0.426). In the second bout, BLa was lower (p = 0.005, ηp2 = 0.602), RPE in the first trial was lower (p = 0.002; d = 0.923), and post exercise perceived soreness of the gastrocnemius, quadriceps, and hamstrings was attenuated (p < 0.002; ηp2 > 0.693). Perceived soreness of the gluteal muscles was lower in the second bout immediately post exercise, 24 h, and 48 h post exercise (p < 0.025; d > 0.922). A repeated bout of downhill running attenuated perceived muscle soreness and may modulate the physiological and perceived physical demand of a second bout of level and downhill running.

Analysis of lower limb muscle strength characteristics of amateur runners with patellofemoral pain: A cross-sectional study.

To analyze the lower limb muscle strength characteristics of amateur runners with patellofemoral pain (PFP). Sixty amateur runners (30 in the knee pain group, 30 in the control group) underwent measurements of hip abduction strength, knee extension strength, and knee flexion strength. Additionally, the hamstring/quadriceps ratio and limb strength symmetry index were calculated for all participants. Statistical analyses were conducted using linear mixed models. The hip abduction and knee extensors strength of amateur runners with PFP was significantly lower than that of the control group. The hamstring/quadriceps ratio was significantly higher in the male knee pain group compared to the control group, while no significant difference was found between the female knee pain group and the control group. Furthermore, both the hip abduction strength symmetry index and knee extensors symmetry index were significantly lower in the knee pain group compared to the control group. Amateur runners with PFP exhibit distinct lower limb strength characteristics compared to non-knee pain runners. Additionally, differences in lower limb strength characteristics between male and female amateur runners with PFP were observed. These findings emphasize the importance of considering functional and gender differences in PFP rehabilitation training.

Impact of aging on maximal oxygen uptake in female runners and sedentary controls

The present study aimed to compare V̇O2max (absolute, adjusted to total body mass, and adjusted to lean mass) in recreational runners and sedentary women < and > 50 yr and verify the effect of aging and physical activity level on the three types of V̇O2 max expression. The study included 147 women:85 runners (45.7 ± 14.1 yr) and 62 sedentary controls (48.8 ± 9.8 yr). They were subjected to cardiopulmonary exercise testing for V̇O2 max measurement and a body composition test by dual-emission X-ray absorptiometry system. V̇O2max were expressed as absolute values (L/min), relative to total body mass values (mL/kg/min), and relative to lean mass values (mL/kgLM/min). The two-way analysis of variance revealed a significant interaction [F(2,131) = 4.43, p < 0.001] and effects of age group [F(2,131) = 32.79, p < 0.001] and physical activity group [F(2,131) = 55.64, p < 0.001] on V̇O2max (mL/min). V̇O2max (mL/kg/min) and V̇O2 max (mL/kgLM/min) were significantly influenced by age and physical activity levels. The multiple regression model explains 76.2 % of the dependent variable V̇O2max (mL/kg/min), age (β = −0.335, t = −7.841, p < 0.001), and physical activity group (β = −0.784, t = −18.351, p < 0.001). In conclusion, female runners had higher V̇O2 max values than sedentary women at all ages, even though aging has a greater impact on V̇O2 max in the runners group. In addition to cardiorespiratory fitness, women's metabolic lean mass function, as measured by V̇O2max adjusted by lean mass, is significantly influenced by aging. Finally, physical activity has a greater impact on V̇O2 max levels than aging.

Technologically advanced running shoes reduce oxygen cost and cumulative tibial loading per kilometer in recreational female and male runners

Technologically advanced running shoes (TARS) improve performance compared to classical running shoes (CRS). Improved race performance has been attributed to metabolic savings in male runners, but it remains unclear if these same benefits are experienced among females and in recreational runners. The mechanisms behind these benefits are still not fully understood despite the need for optimisation, and their influence on injury mechanisms has not been explored. Here we combined biomechanical, physiological, and modelling approaches to analyse joint mechanics, oxygen uptake, and tibial load in nineteen male and female recreational runners running with CRS and TARS at their individual lactate threshold speed (12.4 ± 1.9 km/h). Oxygen uptake was 3.0 ± 1.5% lower in TARS than in CRS. Ankle dorsiflexion, joint moment and joint power were reduced in TARS compared to CRS at various phases of stance including midstance, while knee joint mechanics were mostly similar throughout. There were no significant differences for tibial bending moment during the stance phase but cumulative tibial damage per kilometre was 12 ± 9% lower in TARS compared to CRS. Our results suggest that running with TARS reduces oxygen cost in recreational female and male runners, which may partly be explained by differences in lower limb joint mechanics. The lower cumulative tibial bone load with TARS may allow runners to run longer distances in this type of shoe compared to CRS.

Physiological and Locomotor Profiling Enables to Differentiate Between Sprinters, 400-m Runners, and Middle-Distance Runners.

Thron, M, Woll, A, Doller, L, Quittmann, OJ, Härtel, S, Ruf, L, and Altmann, S. Physiological and locomotor profiling enables to differentiate between sprinters, 400-m runners, and middle-distance runners. J Strength Cond Res 38(8): 1419-1427, 2024-Different approaches exist for characterizing athletes, e.g., physiological and locomotor profiling. The aims of this study were to generate and compare physiological and locomotor profiles of male and female runners and to evaluate relationships between the different approaches. Thirty-four highly trained adolescent and young adult female and male athletes ( n = 11 sprinters; n = 11,400-m runners; n = 12 middle-distance runners) performed two 100-m sprints on a running track to determine maximal sprinting speed (MSS) and maximal lactate accumulation rate (ċLa max ). A cardiopulmonary exercise test was performed on a treadmill to determine maximal aerobic speed (MAS) and maximal oxygen uptake (V̇ o2 max). Anaerobic speed reserve (ASR) was calculated as the difference between MSS and MAS. Group comparisons were conducted with a 2-way ANOVA (discipline × sex; p < 0.05) and Bonferroni post hoc tests and Cohen's d as effect size. Parameters were correlated by Pearson's correlation coefficients. Maximal aerobic speed and V̇ o2 max were higher in 400-m and middle-distance runners compared with sprinters ( p ≤ 0.02; -2.24 ≤ d ≤ -1.29). Maximal sprinting speed and ċLa max were higher in sprinters and 400-m runners compared with middle-distance runners (0.03 ≤ p ≤ 0.28; 0.73 ≤ d ≤ 1.23). Anaerobic speed reserve was highest in sprinters and lowest in middle-distance runners ( p ≤ 0.03; 1.24 ≤ d ≤ 2.79). High correlations were found between ASR and MAS, MSS, and ċLa max ( p < 0.01; -0.55 ≤ r ≤ 0.91) and between ċLa max and MSS ( p < 0.01; r = 0.74). Our results indicate that athletes of different sprinting and running disciplines show differing physiological and locomotor profiles, and that the parameters of these approaches are related to each other. This can be of interest for assessing strengths and weaknesses (e.g., for talent identification) or training prescription in these disciplines.

Gender-based heterogeneity of FAHFAs in trained runners.

Fatty acid esters of hydroxy fatty acid (FAHFA) are anti-diabetic and anti-inflammatory lipokines. Recently FAHFAs were also found to predict cardiorespiratory fitness in a cross-sectional study of recreationally trained runners. Here we report the influences of body composition and gender on static FAHFA abundances in circulation. We compared the association between circulating FAHFA concentrations and body composition, determined by dual x-ray absorptiometry, in female recreational runners who were lean (BMI < 25 kg/m2, n = 6), to those who were overweight (BMI ≥ 25 kg/m2, n = 7). To characterize the effect of gender we also compared circulating FAHFAs in lean male recreational runners (n = 8) to recreationally trained lean female (n = 6) runner group. Circulating FAHFAs were increased in females in a manner that was modulated by specific adipose depot sizes, blood glucose, and lean body mass. As expected, circulating FAHFAs were diminished in the overweight group, but strikingly, within the lean cohort, increases in circulating FAHFAs were promoted by increased fat mass, relative to lean mass, while the overweight group showed a significantly attenuated relationship. These studies suggest multimodal regulation of circulating FAHFAs and raise hypotheses to test endogenous FAHFA dynamic sources and sinks in health and disease, which will be essential for therapeutic target development. Baseline circulating FAHFA concentrations could signal sub-clinical metabolic dysfunction in metabolically healthy obesity.

A VALIDATION OF A NOVEL RUNNING ECONOMY PROTOCOL AND COMPARISON OF TWO CARBON-PLATED RUNNING SHOES IN FEMALE LONG-DISTANCE RUNNERS

INTRODUCTION Running economy (RE) is the strongest predictor of long-distance running performance in well-trained athletes (1). Carbon-plated running shoes have indicated improvements of 4% in RE when compared to previous generation non-carbon-plated running shoes (2). However, these studies have key methodological limitations; the prescribed intensities didn’t replicate race demands, the influence of fatigue was not considered, and testing was only completed on males. AIM: The primary aim of this study was to develop an appropriate protocol to measure RE in female long-distance runners. The secondary aim was to compare performance and RE of two carbon-plated performance shoes in female long-distance runners. METHODS Seven female endurance athletes (age: 30.7 ± 6.6 y, mass: 59.1 ± 5 kg, VO2max: 55.3 ± 4.1 ml/kg/min) completed a graded exercise test to establish a relative race intensity (90% of lactate threshold). Participants completed two testing sessions during the follicular phase of the menstrual cycle in alternating footwear, which consisted of four 7-minute trials, a 25-minute continuous run, four 7-minute trials, and a 13-minute distance trial. RE was recorded as the oxygen consumption and energetic cost of running from minutes 5-7 of each trial. Shoe preference was recorded midway through the first session and the end of the second session. A linear mixed model was used to compare economy and performance metrics. RESULTS There was no significant difference in RE because of fatigue and no significant difference between shoes. However, large individual variations were evident. Participants reported disagreement between preferred shoe and the shoe that demonstrated greatest RE. CONCLUSION A longer protocol that controlled for the menstrual cycle did not induce fatigue related changes in female participants, supporting a higher resistance to fatigue in females (3). The individual variation between shoes suggests that further analyses should be conducted to inform shoe selection for female long-distance runners.

Factors Associated With High-Risk and Low-Risk Bone Stress Injury in Female Runners: Implications for Risk Factor Stratification and Management.

Bone stress injury (BSI) is a common overuse injury in active women. BSIs can be classified as high-risk (pelvis, sacrum, and femoral neck) or low-risk (tibia, fibula, and metatarsals). Risk factors for BSI include low energy availability, menstrual dysfunction, and poor bone health. Higher vertical load rates during running have been observed in women with a history of BSI. The purpose of this study was to characterize factors associated with BSI in a population of premenopausal women, comparing those with a history of high-risk or low-risk BSI with those with no history of BSI. It was hypothesized that women with a history of high-risk BSI would be more likely to exhibit lower bone mineral density (BMD) and related factors and less favorable bone microarchitecture compared with women with a history of low-risk BSI. In contrast, women with a history of low-risk BSI would have higher load rates. Cross-sectional study; Level of evidence, 3. Enrolled were 15 women with a history of high-risk BSI, 15 with a history of low-risk BSI, and 15 with no history of BSI. BMD for the whole body, hip, and spine was standardized using z scores on dual-energy x-ray absorptiometry. High-resolution peripheral quantitative computed tomography was used to quantify bone microarchitecture at the radius and distal tibia. Participants completed surveys characterizing factors that influence bone health-including sleep, menstrual history, and eating behaviors-utilizing the Eating Disorder Examination Questionnaire (EDE-Q). Each participant completed a biomechanical assessment using an instrumented treadmill to measure load rates before and after a run to exertion. Women with a history of high-risk BSI had lower spine z scores than those with low-risk BSI (-1.04 ± 0.76 vs -0.01 ± 1.15; P < .05). Women with a history of high-risk BSI, compared with low-risk BSI and no BSI, had the highest EDE-Q subscores for Shape Concern (1.46 ± 1.28 vs 0.76 ± 0.78 and 0.43 ± 0.43) and Eating Concern (0.55 ± 0.75 vs 0.16 ± 0.38 and 0.11 ± 0.21), as well as the greatest difference between minimum and maximum weight at current height (11.3 ± 5.4 vs 7.7 ± 2.9 and 7.6 ± 3.3 kg) (P < .05 for all). Women with a history of high-risk BSI were more likely than those with no history of BSI to sleep <7 hours on average per night during the week (80% vs 33.3%; P < .05). The mean and instantaneous vertical load rates were not different between groups. Women with a history of high-risk BSI were more likely to exhibit risk factors for poor bone health, including lower BMD, while load rates did not distinguish women with a history of BSI.

Association between Plantar Fasciitis and Hamstring Tightness among Runners

Background: Plantar fasciitis is a prevalent condition among athletes, especially runners, characterized by heel pain and potentially influenced by biomechanical factors such as hamstring tightness. However, the specific relationship between hamstring tightness and plantar fasciitis in athletes has not been extensively studied. Objective: This study aimed to investigate the association between hamstring tightness and plantar fasciitis among runners, to determine whether hamstring tightness contributes to the severity or incidence of plantar fasciitis. Methods: We conducted a cross-sectional study involving 30 athletes diagnosed with plantar fasciitis from sports clubs in Lahore. The study included both male (86.6%) and female (13.4%) runners aged 20 to 45 years. Hamstring tightness was assessed using the Active Knee Extension test. Data were analyzed using Pearson Chi-Square tests in SPSS version 25, with a significance threshold set at p&lt;0.05. Results: The prevalence of hamstring tightness among the athletes was 30%. Statistical analysis revealed no significant association between hamstring tightness and plantar fasciitis (p=0.068), with a Pearson correlation coefficient (r) of -0.48, suggesting a moderate negative correlation. Conclusion: The study concluded that while hamstring tightness is common among runners with plantar fasciitis, it does not significantly influence the occurrence or severity of the condition. Further research is recommended to explore other biomechanical factors that may impact plantar fasciitis in athletic populations.

Effect of Menstrual Cycle on Neuromuscular Efficiency and Muscular Strength in Runners

PURPOSE: The aim of this study was to examine the influence of the menstrual cycle (MC) stages on neuromuscular efficiency and muscular strength in female runners. METHODS: Three runners (females) underwent testing using a BIODEX isokinetic dynamometer concurrently with a BioPac EMG, during which peak torque, peak torque/body weight, time to peak torque, mean amplitude, median amplitude, minimum amplitude, maximum amplitude, frequency, and the p-p value were collected throughout the test. During the test, the performance variables were assessed on the quadriceps (rectus femoris) muscle and collected at speeds of 60 degrees/second and 180 degrees/second. STATISTICAL ANALYSIS: A paired-sample t-test was used to determine the correlation between neuromuscular efficiency and peak torque of the quadriceps during extension in the two MC phases. A paired-sample t-test was also used to determine the difference in neuromuscular efficiency between the MC phases, as well as peak torque between the MC phases. RESULTS: Muscular strength testing did not reveal statistical significance between neuromuscular efficiency and peak torque of the quadriceps during MC phases. Furthermore, there was no statistical significance between the differences in peak torque of the MC phases. Maximum amplitude at 60 degrees/second on the left leg between the MC phases revealed statistical significance (p = 0.026). EMG wave frequency at 60 degrees/second on the right leg between the MC phases revealed statistical significance (p = 0.007). CONCLUSION: Results show a significant difference in maximum amplitude and wave frequency at 60 degrees/second during knee extension between the MC phases.

Risk of Disordered Eating, Exercise Dependence, Body Dissatisfaction, and Fueling Habits in Masters Trail Runners

Introduction: Masters-level trail runners comprise a large percentage of trail and ultramarathon racers. Endurance training may increase the risk of developing disordered eating (DE) patterns and exercise dependence (EXD). This study investigated the risk of DE and EXD in masters-level runners, and compared the risk of EXD, body dissatisfaction, injuries, and fueling habits in runners at risk vs. not at risk for DE.Methods: In this cross-sectional study design, male (n = 457) and female (n = 564) masters trail runners (41-65 years of age) completed a Qualtrics survey comprising the Disordered Eating Screen for Athletes (DESA-6), Exercise Dependence Scale (EDS-21), and questions pertaining to fueling strategies, dietary preferences, and body image satisfaction.Results: 46% of females and 32% of males were at risk for DE based on the DESA-6. 80% of female and 79% of male runners were classified as symptomatic for EXD. For the entire population, there was a significant association between DE risk (88.2%) and symptomatic EXD (χ21 = 32.5, p &lt; 0.001). The majority of participants (71.4%) reported being dissatisfied with their weight.Conclusion: This study demonstrated a high prevalence of DE, EXD, and body dissatisfaction in masters trail runners.

Running Event, Age, and Competitive Level as Predictors of Dual-Energy X-Ray Absorptiometry-Derived Body Composition and Bone Health Markers in Female Runners.

Wilson, LJ and Curtis, C. Running event, age, and competitive level as predictors of dual-energy X-ray absorptiometry-derived body composition and bone health markers in female runners. J Strength Cond Res 38(7): e366-e372, 2024-The aim of this study was to assess the impact of running discipline, competitive level (COMP), and age on body composition measures in female athletes. A total of n = 51 female runners (age: 30.9 ± 5.7 years, stature: 166.7 ± 5.7 cm, and body mass (BM): 57.1 ± 8.2 kg) completed a full-body dual-energy x-ray absorptiometry (DXA) scan in a cross-sectional design. One-way ANOVA or Kruskal-Wallis was used to identify differences in DXA measures and independent variables. Stepwise regression determined the contribution of independent variables on DXA measures. Body fat percentage (BF%) and fat mass (FM) differed based on COMP (BF%: H (2) = 17.451; FM: H (2) = 17.406, both p ≤ 0.0001). Competitive level modestly predicted BF% and FM (BF%: R2adj = 0.316, F (1,50) = 22.660; FM: R2adj = 0.300, F (1,50) = 21.029, both p ≤ 0.0001). Bone mineral density (BMD) and BMD Z-score (BMD Z ) did not differ between age, running discipline, or COMP (age: BMD: F (2,50) = 2.825, BMD Z : F (2,50) = 2.215; running discipline: BMD: F (3,50) = 1.145, BMD Z : F (3,50) = 1.474; COMP: BMD: F (2,50) = 0.074, BMD Z : F (2,50) = 1.297, all p ≤ 0.05). Age and running discipline modestly predicted BMD and BMD Z (BMD: R2adj = 0.179, F (1,50) = 5.264; BMD Z : R2adj = 0.173, F (1,50) = 4.545, both p ≤ 0.05). These findings indicate COMP may be a predictor of BF% and FM. Age and running discipline appear predictors of bone health markers. Such findings may enable medical and sport science practitioners to tailor interventions relating to realization of training adaptations, performance, and health.