Evaluating the contribution of lower extremity kinetics to whole body power output during the power snatch

2017 ◽  
pp. 1-13 ◽  
Author(s):  
Sangwoo Lee ◽  
Kyle D. DeRosia ◽  
Landon M. Lamie
Keyword(s):  
Lower Extremity ◽  
Power Output ◽  
Whole Body

scholarly journals Systematic and Multidisciplinary Evaluation of Fibromuscular Dysplasia Patients Reveals High Prevalence of Previously Undetected Fibromuscular Dysplasia Lesions and Affects Clinical Decisions

Hypertension ◽  
2020 ◽  
Vol 75 (4) ◽  
pp. 1102-1109 ◽  
Author(s):  
Ewa Warchol-Celinska ◽  
Aleksander Prejbisz ◽  
Piotr Dobrowolski ◽  
Anna Klisiewicz ◽  
Jacek Kadziela ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Lower Extremity ◽  
Computed Tomography Angiography ◽  
Fibromuscular Dysplasia ◽  
Vascular Complications ◽  
Arterial Stenosis ◽  
Whole Body ◽  
Clinical Decisions ◽  
Newly Diagnosed ◽  
Vascular Beds

Fibromuscular dysplasia (FMD), regarded as a generalized vascular disease, may affect all vascular beds and may result in arterial stenosis, occlusion, aneurysm, or dissection. It has been proposed to systematically evaluate all vascular beds in patients with FMD, regardless of initial FMD involvement. However, the impact of this approach on clinical decisions and on management is unknown. Within the prospective ARCADIA-POL study (Assessment of Renal and Cervical Artery Dysplasia–Poland), we evaluated 232 patients with FMD lesions confirmed in at least one vascular bed, out of 343 patients included in the registry. All patients underwent a detailed clinical evaluation including computed tomography angiography of intracranial and cervical arteries, as well as computed tomography angiography of the abdominal aorta, its branches, and upper and lower extremity arteries. In the study group, FMD lesions were most frequently found in renal arteries (87.5%). FMD was also found in cerebrovascular (24.6%), mesenteric (13.8%), and upper (3.0%) and lower extremity (9.9 %) arteries. Newly diagnosed FMD lesions were found in 34.1% of the patients, and previously undetected vascular complications were found in 25% of the patients. Among all FMD patients included in the study, one out of every 4 evaluated patients qualified for interventional treatment due to newly diagnosed FMD lesions or vascular complications. The ARCADIA-POL study shows for the first time that the systematic and multidisciplinary evaluation of patients with FMD based on a whole-body computed tomography angiography scan has an impact on their clinical management. This proved the necessity of the systematic evaluation of all vascular beds in patients with FMD, regardless of initial FMD involvement.

Influence of Bicycle Seat Tube Angle and Hand Position on Lower Extremity Kinematics and Neuromuscular Control: Implications for Triathlon Running Performance

2011 ◽  
Vol 27 (4) ◽  
pp. 297-305 ◽  
Author(s):  
Amy Silder ◽  
Kyle Gleason ◽  
Darryl G. Thelen
Keyword(s):  
Lower Extremity ◽  
Neuromuscular Control ◽  
Rectus Femoris ◽  
Body Motion ◽  
Treadmill Running ◽  
Whole Body ◽  
Knee Extensors ◽  
Hand Position ◽  
Plantar Flexors ◽  
Lower Extremity Muscle

We investigated how varying seat tube angle (STA) and hand position affect muscle kinematics and activation patterns during cycling in order to better understand how triathlon-specific bike geometries might mitigate the biomechanical challenges associated with the bike-to-run transition. Whole body motion and lower extremity muscle activities were recorded from 14 triathletes during a series of cycling and treadmill running trials. A total of nine cycling trials were conducted in three hand positions (aero, drops, hoods) and at three STAs (73°, 76°, 79°). Participants also ran on a treadmill at 80, 90, and 100% of their 10-km triathlon race pace. Compared with cycling, running necessitated significantly longer peak musculotendon lengths from the uniarticular hip flexors, knee extensors, ankle plantar flexors and the biarticular hamstrings, rectus femoris, and gastrocnemius muscles. Running also involved significantly longer periods of active muscle lengthening from the quadriceps and ankle plantar flexors. During cycling, increasing the STA alone had no affect on muscle kinematics but did induce significantly greater rectus femoris activity during the upstroke of the crank cycle. Increasing hip extension by varying the hand position induced an increase in hamstring muscle activity, and moved the operating lengths of the uniarticular hip flexor and extensor muscles slightly closer to those seen during running. These combined changes in muscle kinematics and coordination could potentially contribute to the improved running performances that have been previously observed immediately after cycling on a triathlon-specific bicycle.

Determination of Optimal WBV Amplitude and Frequency on Lower Extremity Power Output and EMGrms Activity

2006 ◽  
Vol 38 (Supplement) ◽  
pp. S375
Author(s):  
Nikki J. Hughes ◽  
Chad Harris ◽  
Howard P. Davis ◽  
Kathy D. Browder ◽  
Dennis G. Dolny
Keyword(s):  
Lower Extremity ◽  
Power Output

Mechanical and propelling efficiency in swimming derived from exercise using a laboratory-based whole-body swimming ergometer

2012 ◽  
Vol 113 (4) ◽  
pp. 584-594 ◽  
Author(s):  
Paola Zamparo ◽  
Ian L. Swaine
Keyword(s):  
Power Output ◽  
Power Input ◽  
Mechanical Power ◽  
Whole Body ◽  
Metabolic Power ◽  
Exact Simulation ◽  
Mechanical Power Output ◽  
Propelling Efficiency ◽  
Overall Efficiency ◽  
Active Drag

Determining the efficiency of a swimming stroke is difficult because different “efficiencies” can be computed based on the partitioning of mechanical power output (Ẇ) into its useful and nonuseful components, as well as because of the difficulties in measuring the forces that a swimmer can exert in water. In this paper, overall efficiency (ηO = ẆTOT/Ė, where ẆTOT is total mechanical power output, and Ė is overall metabolic power input) was calculated in 10 swimmers by means of a laboratory-based whole-body swimming ergometer, whereas propelling efficiency (ηP = ẆD/ẆTOT, where ẆD is the power to overcome drag) was estimated based on these values and on values of drag efficiency (ηD = ẆD/Ė): ηP = ηD/ηO. The values of ηD reported in the literature range from 0.03 to 0.09 (based on data for passive and active drag, respectively). ηO was 0.28 ± 0.01, and ηP was estimated to range from ∼0.10 (ηD = 0.03) to 0.35 (ηD = 0.09). Even if there are obvious limitations to exact simulation of the whole swimming stroke within the laboratory, these calculations suggest that the data reported in the literature for ηO are probably underestimated, because not all components of ẆTOT can be measured accurately in this environment. Similarly, our estimations of ηP suggest that the data reported in the literature are probably overestimated.

Anaerobic Cycling Power Output with Variations in Recumbent Body Configuration

2001 ◽  
Vol 17 (3) ◽  
pp. 204-216 ◽  
Author(s):  
Raoul F. Reiser ◽  
Michael L. Peterson ◽  
Jeffrey P. Broker
Keyword(s):  
Lower Extremity ◽  
Body Mass ◽  
Power Output ◽  
Peak Power ◽  
High Performance ◽  
Anaerobic Power ◽  
Average Power ◽  
Knee Joints ◽  
Anaerobic Power Output ◽  
Human Powered

While the recumbent cycling position has become common for high-performance human-powered vehicles, questions still remain as to the influence of familiarity on recumbent cycling, the optimal riding position, and how recumbent cycling positions compare to the standard cycling position (SCP). Eight recumbent-familiar cyclists and 10 recreational control cyclists were compared using the 30-s Wingate test in 5 recumbent positions as well as the SCP. For the recumbent positions, hip position was maintained 15° below the bottom bracket while the backrest was altered to investigate body configuration angle (BCA: the angle between the bottom bracket, hip, and a marker at mid-torso) changes from 100° to 140° in 10° increments. Between-groups analysis found that only 4 of the 126 analyzed parameters differed significantly, with all trends in the same direction. Therefore both groups were combined for further analysis. Whole-group peak power (14.6 W/kg body mass) and average power (9.9 and 9.8 W/kg body mass, respectively) were greatest in the 130° and 140° BCA positions, with power dropping off as BCA decreased through 100° (peak = 12.4 W/kg body mass; avg. = 9.0 W/kg body mass). Power output in the SCP (peak = 14.6 W/kg body mass; avg. = 9.7 W/kg body mass) was similar to that produced in the 130° and 140° recumbent BCA. Average hip and ankle angles increased (became more extended/ plantar-flexed), 36° and 10°, respectively, with recumbent BCA, while knee angles remained constant. The lower extremity kinematics of the 130° and 140° BCA were most similar to those of the SCP. However, SCP hip and knee joints were slightly extended and the ankle joint was slightly plantar-flexed compared to these two recumbent positions, even though the BCA of the SCP was not significantly different. These findings suggest: (a) the amount of recumbent familiarity in this study did not produce changes in power output or kinematics; (b) BCA is a major determinant of power output; and (c) recumbent-position anaerobic power output matches that of the SCP when BCA is maintained, even though lower extremity kinematics may be altered.

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