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Cable resistance training machines are showing resurgent popularity and allow greater number of degrees of freedom than typical selectorized equipment. Given that specific kinetic chains are used during distinct activities of daily living (ADL), cable machines may provide more effective interventions for some ADL, whereas others may be best addressed using selectorized equipment. This study examined differences in activity levels (root mean square of the EMG [rmsEMG]) of 6 major muscles (pectoralis major, PM; anterior deltoid, AD; biceps brachii, BB; rectus abdominis, RA; external obliques, EO; and triceps brachii, TB) and kinematics of multiple joints between a cable and standard selectorized machines during the biceps curl, the chest press, and the overhead press performed at 1.5 seconds per contractile stage. Fifteen individuals (9 men, 6 women; mean age ± SD, 24.33 ± 4.88 years) participated. Machine order was randomized. Significant differences favoring cable training were seen for PM and AD during biceps curl; BB, AD, and EO for chest press; and BB and EO during overhead press (p ≤ 0.05). Greater starting and ending angles were seen for the elbow and shoulder joints during selectorized biceps curl, whereas hip and knee starting and ending angles were greater for cable machine during chest and overhead presses (p < 0.0001). Greater range of motion (ROM) favoring the cable machine was also evident (p < 0.0001). These results indicate that utilization patterns of selected muscles, joint angles, and ROMs can be varied because of machine application even when similar exercises are used, and therefore, these machines can be used selectively in training programs requiring specific motor or biomechanical patterns. [ABSTRACT FROM AUTHOR]

Unlabelled: Power-based resistance training (PWT), using low load and high velocity, can improve physical function and quality of life in older persons. Patients with Parkinson's disease (PD), exhibiting muscular weakness and reduced movement speed, have been shown to be benefit from resistance training; however, little is known about the advantages of PWT for PD.Purpose: To evaluate the effects of PWT on bradykinesia and muscular performance in older patients with PD.Methods: Twenty-six patients with mild to moderate PD were randomly assigned to a PWT or control group (CON). The PWT program was three months, incorporating two sessions/wk of high-speed resistance training combined balance and agility drills. Outcome measures included: upper and lower limb bradykinesia scores, one repetition maximums (1RM) and peak powers on biceps curl, chest press, leg press, hip abduction and seated calf, and quality of life (PDQ-39).Results: The PWT group produced significant improvement in both upper and lower limbs bradykinesia scores, 1RM and muscle peak power (p < .05), which surpassed the CON group except for power during the seated calf exercise. No significant correlations between changes in clinical measure of bradykinesia and muscle peak power were observed after training. Significant improvements were seen in the PDQ-39 overall score, subsections for mobility, activities of daily living and social support for the PWT group.Conclusion: The 3-month PWT program significantly reduced bradykinesia and increased muscle strength and power in older patients with PD. Power training is an effective training modality to improve physical function and quality of life for PD. [ABSTRACT FROM AUTHOR]

We developed a physical exercise intervention aimed at improving multiple determinants of physical performance in severe mental illness. A sample of 12 (9M, 3F) overweight or obese community-dwelling patients with schizophrenia ( n =9) and bipolar disorder ( n =3) completed an eight-week, high-velocity circuit resistance training, performed twice a week on the computerized Keiser pneumatic exercise machines, including extensive pre/post physical performance testing. Participants showed significant increases in strength and power in all major muscle groups. There were significant positive cognitive changes, objectively measured with the Brief Assessment of Cognition Scale: improvement in composite scores, processing speed and symbol coding. Calgary Depression Scale for Schizophrenia and Positive and Negative Syndrome Scale total scores improved significantly. There were large gains in neuromuscular performance that have functional implications. The cognitive domains that showed the greatest improvements (memory and processing speed) are most highly predictive of disability in schizophrenia. Moreover, the improvements seen in depression suggest this type of exercise intervention may be a valuable add-on therapy for bipolar depression. [ABSTRACT FROM AUTHOR]

Gait analysis is used in research and clinical environments; yet several limitations exist in current methodologies. Markerless systems, utilizing high-speed video and artificial intelligence, eliminate most limitations encountered in marker-, depth-, or inertial sensor-based systems; however, further development is needed to improve their utility and accessibility in practice. Spatiotemporal parameters from 22 young adults were estimated during over-ground gait. Nine parameters were calculated using events determined from force plate information combined with foot segment tracking and from motion of the foot relative to the sacrum using marker-based and markerless tracking. Two-way mixed effects, single measurement, absolute agreement and relative consistency interclass correlation coefficients, Bland-Altman bias and limits of agreement, and Lin's concordance correlations were used to examine the validity of parameters from markerless tracking compared to parameters calculated from gait event methods using force plates and marker-based tracking. Gait speed, stride length, step length, cycle time, and step time from the markerless system all showed strong agreement with the force plate method. Other markerless-determined parameters were not as accurate. Differences in stride width are attributable to inconsistencies in foot segment definitions between models; while differences in stance time, swing time, and double limb support time were influenced by gait event methods. Mean differences in gait parameters were smaller than meaningful clinical differences in Parkinson's disease patients and within ranges of reference values for elderly subjects. Further studies are needed to determine the validity across other patient groups, but results support the continued development of markerless systems for over-ground gait analysis. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To compare muscle activation patterns in 14 dominant side muscles during different yoga poses across three skill levels. DESIGN: Mixed repeated-measures descriptive study. SETTING: University neuromuscular research laboratory, Miami, US. PARTICIPANTS: A group of 36 yoga practitioners (9 M/27 F; mean±SD, 31.6±12.6 years) with at least 3 months yoga practice experience. INTERVENTIONS: Each of the 11 surya namaskar poses A and B was performed separately for 15s and the surface electromyography for 14 muscles were recorded. MAIN OUTCOME MEASURES: Normalized root mean square of the electromyographic signal (NrmsEMG) for 14 muscles (5 upper body, 4 trunk, 5 lower body). RESULTS: There were significant main effects of pose for all fourteen muscles except middle trapezius (p<.02) and of skill level for the vastus medialis; p=.027). A significant skill levelxpose interaction existed for five muscles (pectoralis major sternal head, anterior deltoid, medial deltoid, upper rectus abdominis and gastrocnemius lateralis; p<.05). Post hoc analyses using Bonferroni comparisons indicated that different poses activated specific muscle groups; however, this varied by skill level. CONCLUSION: Our results indicate that different poses can produce specific muscle activation patterns which may vary due to practitioners' skill levels. This information can be used in designing rehabilitation and training programs and for cuing during yoga training. [ABSTRACT FROM AUTHOR]

The purpose of this pilot study was to evaluate the effectiveness of whole body vibration (WBV) training as a modality for inducing changes in body composition, cardiovascular condition, and muscular strength in sedentary postmenopausal women. WBV training was compared with other training regimens, ie, aerobic training and circuit resistance training, commonly used to promote weight loss, cardiovascular conditioning, and muscular strength. Postmenopausal women (aged 48-60 years) were randomly assigned to WBV training, circuit resistance training, or aerobic training. Participants trained three times per week for 8 weeks. The training regimens were progressive in nature, with increases in training intensity and duration occurring throughout the 8-week period. Body composition was assessed using dual-energy X-ray absorptiometry analyses. A modified Bruce treadmill protocol was used to assess aerobic capacity (VO2peak) and time to peak exhaustion. Upper and lower body strengths were determined by one repetition maximum (1-RM) chest and leg presses, respectively. Variables were analyzed using separate 3 (exercise mode) × 2 (time) repeated-measures analysis of variance with effect sizes due to the small sample size. No significant main effects or interactions were seen for any body composition variable; however, moderate to large effect sizes (η2=0.243 and η2=0.257) were detected regarding interactions for percent body fat and lean body mass favoring aerobic training and circuit resistance training. For VO2peak, no significant main effects or interactions were detected (time, η2=0.150; P=0.11; time × group, η2=0.139; P=0.30); but a significant time effect was observed for time to peak exhaustion (η2=0.307; P=0.017). A significant interaction for upper body strength (η2=0.464; P=0.007), and main effect for time in lower body strength (η2=0.663; P=0.0001) was detected. Post hoc analysis indicated a significant increase in upper body strength for circuit resistance training (P=0.023) and a decrease for WBV training (P=0.015). Our results indicate that WBV may not be an effective alternative to traditional training with regard to body composition or aerobic capacity, but could have a positive impact on lower body strength. [ABSTRACT FROM AUTHOR]

Background. Power is critical to mobility and activities of daily living and is a key determinant of independence and falls prevention. Therefore, the quantification of power in older persons is critical. The power tests currently available are often expensive, potentially dangerous, and not reflective of everyday activities. We present a modification of an existing field test that uses ambulation up a standard access ramp to quantify functional power in older individuals. Methods. Three hundred sixty-three women and 157 men, aged 73.1 ± 7.0 years, ambulated up a standard access ramp (1:12 rise/run ratio) as quickly as possible. Each person performed one practice and two timed trials. Results. Comparisons with accepted power measures and reported patterns of change with aging supported the validity of the ramp power test. The test was found to be reliable across multiple trials and days. Pair-wise comparisons showed that for women the test was sensitive to differences in power output by half-decade, whereas for men it could distinguish between 9 of the 15 comparisons among age groups. Percentile scores are reported by half-decade for power in both genders. In > 1200 trials performed during this study, only one injury (a slightly strained hamstring) occurred. Conclusions. The ramp power test is valid and reliable and can safely distinguish power by half-decade in women and among the majority of age groups in men. Its safety, low cost, and ease of administration make it a feasible diagnostic tool to assess functional power levels in ambulatory older persons. [ABSTRACT FROM AUTHOR]

Periodization is the most effective approach to resistance training; however, optimal cycle lengths for older persons are not known. This study examined the durations of performance increments, plateaus, and decrements in women, ages 61–75 yr, over 9 wk of isokinetic training. After a 2-wk adaptation cycle, older women trained for either power (PWR; 4.73 rad/s; n = 9) or strength (STR; 1.05 rad/s; n = 8), 3 days/wk with a 1-day recovery between sessions. Repetitions were initially selected to equilibrate work volume between groups. Average power (AP), peak torque (PT), and total work (TW) curves were analyzed using forward and backward stepwise regression to ascertain inflections and plateaus. PWR training produced the highest AP, whereas STR produced the highest FT. TW was similar between groups. The AP curves of the PWR group initially showed a steep positive slope and then plateaued during week 3. The right leg plateau lasted throughout training, whereas the left leg showed another positive inflection during weeks 7 and 8. PWR group TW curves showed positive slopes throughout training. STR group PT curves for both legs showed initial positive slopes peaking between weeks 3 and 4 and declining thereafter. The TW curves for both legs showed slight negative slopes across the first 2 wk, steep positive slopes during weeks 3–6, and a final plateau. Because improvements plateau early during PWR and STR training, isokinetic training prescriptions for optimizing strength and power improvements in older persons should use cycles of 3–4 wk to maximize gains. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence indicates that microvascular alterations in the brain, especially at the capillary level, are one of the major contributors to cognitive impairment and dementia in older adults. The brain and retinal microvasculature share similar anatomic and physiologic features. Alterations of retinal microvasculature reflect similar changes in brain. We examined the associations between retinal microvascular density, cognition and physical fitness in healthy older adults with no reported cognitive decline. Method: Twenty cognitively normal older adults (age: 70.3 ± 4.6 years) were recruited. Both eyes of each subject were imaged using optical coherence tomography angiography. The vessel density of the retinal vascular network (RVN), superficial vascular plexus (SVP), and deep vascular plexus (DVP) was measured. Cognitive function was tested using the Mini‐mental state examination (MMSE) and Montreal Cognitive Assessment (MoCA), while physical performance was evaluated using the YMCA cycle ergometer test. Partial correlations (rpartial) were computed between measures of retinal microvascular density, cognitive function, and physical performance. Result: The MoCA was significantly correlated to vessel density of RVN (rpartial = 0.54, P = 0.002) and SVP (rpartial = 0.59, P < 0.001), but not DVP (rpartial = ‐0.01, P = 0.99). MoCA also showed a trend toward correlation with YMCA total work (TW‐YMCA, rpartial = 0.28, P = 0.14). Retinal microvascular density was not related to TW‐YMCA (rpartial= ‐ 0.23 ∼ 0.12, P > 0.05). Conclusion: The MoCA was significantly correlated to vessel density of RVN (rpartial = 0.54, P = 0.002) and SVP (rpartial = 0.59, P < 0.001), but not DVP (rpartial = ‐0.01, P = 0.99). MoCA also showed a trend toward correlation with YMCA total work (TW‐YMCA, rpartial = 0.28, P = 0.14). Retinal microvascular density was not related to TW‐YMCA (rpartial= ‐ 0.23 ∼ 0.12, P > 0.05). [ABSTRACT FROM AUTHOR]

The KinaTrax markerless motion capture system, used extensively in the analysis of baseball pitching and hitting, is currently being adapted for use in clinical biomechanics. In clinical and laboratory environments, repeatability is inherent to the quality of any diagnostic tool. The KinaTrax system was assessed on within- and between-session reliability for gait kinematic and spatiotemporal parameters in healthy adults. Nine subjects contributed five trials per session over three sessions to yield 135 unique trials. Each trial was comprised of a single bilateral gait cycle. Ten spatiotemporal parameters for each session were calculated and compared using the intraclass correlation coefficient (ICC), Standard Error of the Measurement (SEM), and minimal detectable change (MDC). In addition, seven kinematic waveforms were assessed from each session and compared using the coefficient of multiple determination (CMD). ICCs for between-session spatiotemporal parameters were lowest for left step time (0.896) and left cadence (0.894). SEMs were 0.018 (s) and 3.593 (steps/min) while MDCs were 0.050 (s) and 9.958 (steps/min). Between-session average CMDs for joint angles were large (0.969) in the sagittal plane, medium (0.554) in the frontal plane, and medium (0.327) in the transverse plane while average CMDs for segment angles were large (0.860), large (0.651), and medium (0.561), respectively. KinaTrax markerless motion capture system provides reliable spatiotemporal measures within and between sessions accompanied by reliable kinematic measures in the sagittal and frontal plane. Considerable strides are necessary to improve methodological comparisons, however, markerless motion capture poses a reliable application for gait analysis within healthy individuals. [ABSTRACT FROM AUTHOR]

Velocity-based training (VBT) positively impacts muscle morphology and performance in persons with Parkinson's disease (PD); however, optimal training frequencies for VBT in patients with PD remain undetermined. Changes in ultrasound-determined muscle thickness (MT) and echo intensity (EI)-derived muscle quality of the rectus femoris (RF) and vastus lateralis (VL), neuromuscular performance, and functional capacity were examined following 2 VBT frequencies (2-3 d·wk-1) using 30% velocity loss thresholds for 12 weeks. Neuromuscular performance was assessed using computerized pneumatic resistance machines. For each variable, 2 (time) 3 2 (group) repeated-measures analyses of variance (ANOVA) were used to determine significant main effects and interactions. Significant time effects were seen for MT and EI of all muscles (p, 0.05). Muscle thickness improvements included right VL (RVL) (0.171 6 0.065 cm; p 5 0.019), left VL (LVL) (0.214 6 0.101 cm; p 5 0.049), right RF (RRF) (0.194 6 0.077 cm; p 5 0.023), and left RF (LRF) (0.318 6 0.109 cm; p 5 0.010). For EI, improvements occurred in RVL (218.688 6 3.600; p5,0.001), LVL (210.959 6 4.894; p 5 0.040), RRF (29.516 6 3.537; p 5 0.016), and LRF (29.018 6 3.444; p 5 0.019). Time effects were seen for leg-press 1-repetition maximum and peak power (p, 0.01) and habitual walking speed (p 5 0.022), with a group by time interaction for maximal gait speed favoring the 3 d·wk-1 condition (δ0.15 m·s21, p 5 0.002). The results indicate that VBT at 2 or 3 d·wk-1 can significantly improve muscle morphology, neuromuscular performance, and functional capability in patients with PD; however, improvements in maximal gait speed require 3 d·wk21. These findings provide flexibility when developing exercise prescriptions for patients with PD. [ABSTRACT FROM AUTHOR]

The Nordic hamstring curl appears effective in reducing the incidence of injury in physically active young adults, likely through its capacity as an eccentric exercise to increase muscle stiffness. Although eccentric exercises have been shown to increase muscle stiffness, medium- and long-term Nordic hamstring curl training programs have not demonstrated an effect on muscle stiffness. This study examined the acute effects of a single session of Nordic hamstring curls on the stiffness of the biceps femoris, semitendinosus, and semimembranosus muscles using ultrasound shear wave elastography, an accepted method for measuring passive muscle stiffness. Twenty physically active adults (ages 19–27 years) were randomly assigned to either the Nordic hamstring curl group (n = 10) or the control group (n = 10). Shear wave elastography was performed on the dominant kicking leg for both groups. The exact location of the probe was marked to ensure the same area was assessed during post-testing. Both groups performed a 5-minute cycle ergometer warm-up followed by three 30-second standing static stretches. The Nordic hamstring curl group then performed three sets of six repetitions of the eccentric phase of the Nordic hamstring curl with 1-minute rest intervals between sets. All subjects then rested for five minutes before shear wave elastography was performed. Repeated measures ANOVA revealed no significant main effects or interactions for the biceps femoris or semitendinosus (p >0.05). However, analysis of the semimembranosus was inconclusive due to variability of measurement values. These results are in agreement with findings indicating that long- and short-term Nordic hamstring curl training has no impact on hamstring stiffness, although the effects of Nordic hamstring curl on reducing the probability of hamstring injury are still valid. [ABSTRACT FROM AUTHOR]

A new approach, Combinational Spectral Band Activation Complexity (CSB-AC), that extracts the neuromuscular firing dynamics of surface electromyography (sEMG) signals by applying entropic methods in a multi-dimensional fashion by analyzing the signals temporally, spectrally, and intensity dynamics simultaneously is presented. The CSB-AC signal processing approach introduces a methodology that highlights that a small amount of key fiducial points embedded within the sEMG, 1000x reduction in EMG data, are only needed to show statistically significant changes of the neuromuscular firing dynamics. CSB-AC was compared to the more generalized sample entropy method to demonstrate physiological differences between cohorts and baseline mapping between the two measurements. Results indicated significant differences between CSB-AC and sample entropy regardless of age groups for tibialis anterior and plantar flexion muscles (gastrocnemius medialis, gastrocnemius lateralis, and soleus). Significant differences were found between older and younger subject groups for the gastrocnemius medialis and soleus with the older adults having higher complexity values. CSB-AC produces greater complexity than sample entropy, where this sparser set of data holds paramount information for describing neuromuscular firing and should not be ignored. CSB-AC, accomplishes this by simultaneously assessing the complexity of sEMG's time, intensity, and spectral content, where latent properties of neuromuscular dynamics within this unique set of sparse sEMG data points are critical to characterizing neuromuscular firing. [ABSTRACT FROM AUTHOR]