Frontal Plane Range of Motion Differences in Unilateral and Bilateral Battle Rope Sets: A Pilot Study

Battle rope exercises are commonly used among cross-fitters to build overall muscular strength and cardiorespiratory endurance. Although this training method is physically demanding, no studies have examined the frontal plane movements in the lower extremities when performing battle ropes exercises in their different variations. PURPOSE: The objective of this research was to compare the frontal plane range of motion (ROM) along with the peak joint angles of the ankle, knee, and hip when performing bilateral and unilateral battle ropes exercises. METHODS: Participants with at least six months of resistance training experience performed four sets of bilateral and unilateral battle ropes in a randomized order. The hip, knee, and ankle joint angles were measured using motion-capturing cameras and retroreflective markers placed on the participant’s body. Additionally, the sequence of the angles was measured from the top to bottom motion of the right hand during both unilateral and bilateral activities. RESULTS: The frontal ankle ROM during unilateral measured 2.1 degrees (peak ankle eversion of -5.2 degrees), while during the bilateral battle rope, there was a 1.0 degrees ROM (peak ankle eversion of -3.6 degrees). Additionally, the frontal knee ROM during bilateral battle rope exercises was 4.0 degrees (peak knee adduction of 3.5 degrees), slightly greater than the unilateral battle rope ROM of 3.6 degrees (peak knee adduction of 2.7 degrees). However, in contrast to the ankle and knee, the hip exhibited a significantly greater ROM of 5.9 degrees (peak hip abduction of -17.8 degrees) during unilateral battle rope exercise, as opposed to the 1.8 degrees of ROM (peak hip abduction of -13.7 degrees) during bilateral battle rope exercise. CONCLUSION: This study identified that the hip range of motion was significantly increased when performing unilateral battle rope exercise as opposed to bilateral exercise. The performance of a unilateral battle rope demands a greater side-to-side shift in the frontal plane, requiring the hip joints to accommodate the movements. An increased level of muscular activation in the hip adductors is needed to control the increased range of motion and joint position within the hip joint when performing unilateral battle ropes activities, which involves an increased side to side shifting motion

The Effects of Unilateral and Bilateral Battle Rope Exercise on the Lower Extremity Joint Force: A Pilot Study

The battle rope exercise recently has increased its popularity due to cross fit gyms implementing it into the workout programs. Individuals use this workout to strengthen their upper body, however it is unknown how different modalities of using the battle ropes affects the lower extremity joint force required to stabilize the body. PURPOSE: To examine the effects of unilateral and bilateral battle ropes exercises on lower extremity joint force. METHODS: Subjects performed four bilateral battle rope trials and four unilateral battle rope trials. The trials consisted of twenty seconds of continuous activity with three minutes of rest in between during a single visit to the lab. Lower extremity joints were tracked using a Qualisys motion capture system and Bertec force platforms. Joint force data (normalized to body mass) and ground reaction force (reported in Newtons, both in the medial-lateral axis) were analyzed in the down phase of the movement (from peak rope height to the bottom of the motion). RESULTS: There was decreased lateral force in the hip joint during the bilateral exercise for the left hip (0.601BM) and the right hip (0.586BM) compared to the unilateral (0.803BM and 0.614BM, respectively). However, the knee and ankle showed decreased lateral force during the unilateral exercise (0.376BM and 0.200BM for the left and right knee, respectively and 0.829BM and 1.052BM for the left and right ankle respectively) compared to the bilateral exercise (0.569BM and 0.336BM for the left and right knee, respectively and 1.047BM and 1.145BM for the left and right ankle, respectively). The bilateral exercise showed increased medially-directed forces in the right limb (133.4N) and left limb (148.7N) -compared to the unilateral (109.3N and 110.1N, respectively). CONCLUSION: The results show a discrepancy in terms of medial-lateral joint force. The unilateral exercise shows increased lateral stress on the hip joints while the bilateral shows an increased lateral stress on the ankle and knee. During unilateral exercises, the non-active side (side without the moving arm) hip and knee show increased lateral forces while the active-side ankle shows increased lateral forces. Lower extremity joint position should be considered when using these activities due to their impact on joint force experienced in the lower extremities

Hadronic ψ\psi production calculated in the NRQCD factorization formalism

The NRQCD factorization formalism of Bodwin, Braaten, and Lepage prescribes how to write quarkonium production rates as a sum of products of short-distance coefficients times non-perturbative long-distance NRQCD matrix elements. We present, in the true spirit of the factorization formalism, a detailed calculation of the inclusive cross section for hadronic $\psi$ production. We find that in addition to the well known {\it color-singlet} production mechanisms, there are equally important mechanisms in which the $c\bar{c}$ pair that forms the $\psi$ is initially produced in a {\it color-octet} state, in either a ${}^3S_1$, ${}^1S_0$, ${}^3P_0$ or ${}^3P_2$ angular-momentum configuration. In our presentation, we emphasize the ``matching'' procedure, which %is the method that allows us to determine the short-distance coefficients appearing in the factorization formula. We also point out how one may systematically include relativistic corrections in these calculations.Comment: 25 pages, 3 postscript figures, use Revtex and epsfig.sty We fixed some typos, added some text regarding a reference, and changed some equations. The file will be available at http://phenom.physics.wisc.edu

Comparing Knee Kinetics and Muscular Activity between the Barbell Squat and Flywheel Squat in Recreationally Trained Females

Previous literature has supported flywheel (FW) training with inducing muscular size and strength comparable to resistance training with free weights. However, it remains unclear how the biomechanical demands of these two training methods differ regarding reducing the risk of load-dependent injuries. PURPOSE: With the growing population of female astronauts, this study aimed to compare knee joint kinetics and muscle activation when squatting to full depth on the barbell back (BB) squat and a gravity-independent FW device utilizing technology to be deployed in future long-term space missions. METHODS: Twenty recreationally trained females (22.3 ± 2.7 yrs, 1.6 ± 0.1 m, 59.8 ± 6.8 kg) with at least two years of experience in BB squat training participated in this study. The first session involved one-repetition maximum (1RM) testing on the BB squat and familiarizing the participants with squatting on the FW device (YoYo ™ Multigym). In session two, the participants conducted: 1) one set of seven repetitions at 83% of their 1 RM in the BB and 2) one set of seven maximal repetitions on the FW training device using an inertial load of 0.100 kg ⋅ m2. The order of the exercises in session two was randomized. Three-dimensional motion capture, force platforms, and electromyography assessed knee joint moments and muscle activation on the participants\u27 dominant limb. Paired t-tests were conducted to compare these variables, with a significance set at p ≤ 0.05. RESULTS: Analysis revealed peak knee extensor moments were greater in the BB squat (BB: 2.14 ± 0.36 Nm/kg, p = 0.004; FW: 1.94 ± 0.06 Nm/kg). The BB squat elicited greater mean muscle activity over the set compared to FW squats in the following: (vastus lateralis: +5.68%, p = 0.015; bicep femoris: +4.63%, p \u3c 0.001; gluteus maximus: +4.67%, p = 0.024; gluteus medius: +2.75%, p = 0.011; gastrocnemius lateralis: +3.09%, p = 0.028; gastrocnemius medius: +2.48%, p = 0.024). However, FW squats attained greater tibialis anterior activity (+5.56%, p = 0.04). There was no significant difference in muscle activity observed in the rectus femoris and vastus medialis. CONCLUSION: Although FW training requires less mechanical demand on the knee extensors when squatting to similar depths, participants achieved greater muscular activation during the BB squat

Status and promise of particle interferometry in heavy-ion collisions

After five years of running at RHIC, and on the eve of the LHC heavy-ion program, we highlight the status of femtoscopic measurements. We emphasize the role interferometry plays in addressing fundamental questions about the state of matter created in such collisions, and present an enumerated list of measurements, analyses and calculations that are needed to advance the field in the coming years

Leptoproduction of J/psi

We study leptoproduction of $J/\psi$ at large $Q^2$ within the nonrelativistic QCD (NRQCD) factorization formalism. The cross section is dominated by color-octet terms that are of order $\alpha_s$. The color-singlet term, which is of order $\alpha^2_s$, is shown to be a small contribution to the total cross section. We also calculate the tree diagrams for color-octet production at order $\alpha^2_s$ in a region of phase space where there is no leading color-octet contribution. We find that in this regime the color-singlet contribution dominates. We argue that non-perturbative corrections arising from diffractive leptoproduction, higher twist effects, and higher order terms in the NRQCD velocity expansion should be suppressed as $Q^2$ is increased. Therefore, the color-octet matrix elements $$and$$ can be reliably extracted from this process. Finally, we point out that an experimental measurement of the polarization of leptoproduced $J/\psi$ will provide an excellent test of the NRQCD factorization formalism.Comment: 33 pages latex. 10 figures. Uses revtex, epsf, and rotate macros. This paper is also available via the UW phenomenology archives at http://phenom.physics.wisc.edu/pub/preprints

Hair follicle epidermal stem cells define a niche for tactile sensation

The heterogeneity and compartmentalization of stem cells is a common principle in many epithelia, and is known to function in epithelial maintenance, but its other physiological roles remain elusive. Here we show transcriptional and anatomical contributions of compartmentalized epidermal stem cells in tactile sensory unit formation in the mouse hair follicle. Epidermal stem cells in the follicle upper-bulge, where mechanosensory lanceolate complexes innervate, express a unique set of extracellular matrix (ECM) and neurogenesis-related genes. These epidermal stem cells deposit an ECM protein called EGFL6 into the collar matrix, a novel ECM that tightly ensheathes lanceolate complexes. EGFL6 is required for the proper patterning, touch responses, and αv integrin-enrichment of lanceolate complexes. By maintaining a quiescent original epidermal stem cell niche, the old bulge, epidermal stem cells provide anatomically stable follicle–lanceolate complex interfaces, irrespective of the stage of follicle regeneration cycle. Thus, compartmentalized epidermal stem cells provide a niche linking the hair follicle and the nervous system throughout the hair cycle

A Single Centre Randomised Control Study to Assess the Impact of Pre-Operative Carbohydrate Loading on Women Undergoing Major Surgery for Epithelial Ovarian Cancer

Objective Historically, patients have fasted before elective surgery to ensure an empty stomach to avoid aspiration. A fasting-induced catabolic state however may adversely influence recovery after surgery. Our study was designed to test the effect of oral carbohydrate loading on clinical parameters in patients undergoing major surgery for advanced-stage ovarian cancer. Methods A double-blinded single-centre randomised trial was designed to recruit 110 patients with advanced-stage epithelial ovarian cancer undergoing either primary surgery, or neoadjuvant chemotherapy prior to debulking surgery. Following written informed consent, the patients were randomised into two groups. Group 1 received the carbohydrate drink (intervention) and group 2 received flavoured water (placebo). The quantity of fluid in both groups was 800ml the night before the surgery and 400ml two hours before the induction of anaesthesia. The primary endpoint of the study was the Length of Hospital Stay (LoHS); the secondary parameters assessed were pain scores, nausea and vomiting scores, bowel function, and postoperative complication rate. Results Between March 2009 and December 2011, 80 patients were randomised and 75 completed the study. A decision was made to close the trial early as a change in routine clinical practice meant that patients were admitted on the day of surgery rather than a day before. Analysis of the data revealed that there were no significant differences between the study groups in terms of LoHS and other clinical parameters. Conclusion In this single-center study, which failed to recruit the planned number of patients, we were unable to demonstrate that oral carbohydrate intake pre-operatively has significant impact on the recovery process or the length of hospitalisation postoperatively. Future studies should examine all aspects of an Enhanced Recovery Program after Surgery as a package as compared to a single element to enhance patient outcome. [Abstract copyright: Copyright © 2020, Al-Hirmizy et al.