Effect of Aerobic or Resistance Exercise, or Both, on Intermuscular and Visceral Fat and Physical and Metabolic Function in Older Adults With Obesity While Dieting.

BACKGROUND: Obesity exacerbates age-related effects on body composition and physical and metabolic function. Which exercise mode is most effective in mitigating these deleterious changes in dieting older adults with obesity is unknown. METHODS: In a randomized controlled trial, we performed a head-to-head comparison of aerobic (AEX), resistance (REX), or combination (COMB) exercise during matched ~10% weight loss in 160 obese older adults. Prespecified analyses compared 6-month changes in intermuscular adipose tissue (IMAT) and visceral adipose tissue (VAT) assessed using MRI, insulin sensitivity index (ISI) by oral glucose tolerance test, physical function using Modified Physical Performance Test (PPT), VO2peak, gait speed, and knee strength by dynamometry. RESULTS: IMAT and VAT decreased more in COMB than AEX and REX groups (IMAT; -41% vs -28% and -23% and VAT: -36% vs -19% and -21%; p = .003 to .01); IMAT and VAT decreased in all groups more than control (between-group p < .001). ISI increased more in COMB than AEX and REX groups (86% vs 50% and 39%; p = .005 to .03). PPT improved more in COMB than AEX and REX groups, while VO2peak improved more in COMB and AEX than REX group (all p < .05). Knee strength improved more in COMB and REX than AEX group (all p < .05). Changes in IMAT and VAT correlated with PPT (r = -0.28 and -0.39), VO2peak (r = -0.49 and -0.52), gait speed (r = -0.25 and -0.36), and ISI (r = -0.49 and -0.52; all p < .05). CONCLUSIONS: Weight loss plus combination aerobic and resistance exercise was most effective in improving ectopic fat deposition and physical and metabolic function in older adults with obesity.

High-Velocity Quadriceps Exercises Compared to Slow-Velocity Quadriceps Exercises Following Total Knee Arthroplasty: A Randomized Clinical Study.

BACKGROUND AND PURPOSE: Despite improvement in pain and perceived function in older adults following total knee arthroplasty (TKA), objective outcome measures of muscular impairment and ambulatory function demonstrate significant deficits. Evidence suggests that quadriceps power may play a greater role in ambulatory function than measures of strength alone following TKA. The purpose of this study was to compare the effect of high-velocity (HV) quadriceps exercises with that of slow-velocity (SV) quadriceps exercises on functional outcomes and quadriceps power following TKA. METHODS: This study was a randomized clinical study conducted in an outpatient physical therapy clinic. Twenty-one participants who were 4 to 6 weeks post unilateral TKA were randomly assigned to an HV or SV group. Participants performed an evidence-based standardized progressive resistance exercise program in addition to HV quadriceps exercises or SV quadriceps exercises. Participants attended 2 sessions per week for 8 weeks. Before and after the 8-week exercise intervention, participants completed a functional questionnaire, health survey, functional testing, and underwent quadriceps strength and power testing. RESULTS: Both groups demonstrated improvements in ambulatory outcome measures, strength, speed, and power. The HV group demonstrated significantly greater improvements in distance walked and quadriceps strength than the SV group. LIMITATIONS: These data should be considered preliminary because of a small sample size. CONCLUSION: HV quadriceps exercises may be an effective rehabilitation strategy in conjunction with a standardized progressive resistance exercise program beginning 4 to 6 weeks after TKA.

Current evidence demonstrates similar effects of kilohertz-frequency and low-frequency current on quadriceps evoked torque and discomfort in healthy individuals: a systematic review with meta-analysis.

BACKGROUND: Neuromuscular electrical stimulation (NMES) is widely utilized to enhance muscle performance. However, the optimal NMES waveform with respect to treatment effect has not been established. OBJECTIVE: To investigate the effects of kilohertz-frequency alternating current (KFAC) and low-frequency pulsed current (PC) on quadriceps evoked torque and self-reported discomfort. DATA SOURCES: PubMed, The Cochrane Library, EMBASE, MEDLINE, Physiotherapy Evidence Database (PEDro), SinoMed, ISI Web of Knowledge, and CINAHL were searched for randomized controlled trials (RCTs) and quasi-randomized controlled trials (QRCTs). STUDY SELECTION: Two reviewers independently selected potential studies according to the inclusion criteria, extracted data, and assessed methodological quality. DATA EXTRACTION AND SYNTHESIS: Studies were eligible if they compared KFAC versus PC interventions. Studies that included outcome measures for percentage of maximal isometric voluntary contraction (%MIVC) torque and self-reported discomfort level were eligible for evaluation. Seven studies involving 127 individuals were included. The methodological quality of eligible trials was moderate, with a mean of 5 on the 10-point PEDro scale. Overall, PC was no better than KFAC in terms of evoked torque and there was no difference in self-reported discomfort level. CONCLUSION: KFAC and PC have similar effects on quadriceps evoked torque and self-reported discomfort level in healthy individuals. The small number and overall methodological quality of currently available studies included in this meta-analysis indicate that new RCTs are needed to better determine optimal NMES treatment parameters.

Relative Importance of Four Muscle Groups for Indoor Rock Climbing Performance.

Little research is available to guide training programs for rock climbers. To help meet this need, we sought to determine the relative importance of 4 muscle groups for rock climbing performance. Eleven male climbers were familiarized with an indoor climbing route before 5 separate days of testing. On testing days, subjects were randomly assigned to climb with no prefatiguing exercise (control climb) or after a prefatiguing exercise designed to specifically target the digit flexors (DF), shoulder adductors (SA), elbow flexors (EF), or lumbar flexors (LF). Immediately after the prefatiguing exercise, the subject climbed the route as far as possible without rest until failure. The number of climbing moves was recorded for each climb. Surface electromyography of the target muscles was recorded during the prefatigue. Fewer climbing moves were completed after prefatigue of the DF (50 ± 18%) and EF (78 ± 22%) (p ≤ 0.05) compared with the control climb. The number of moves completed after prefatigue of the LF and SA were not statistically significant compared with the control climb (p > 0.05). The short time lapse between the end of prefatiguing exercise and the start of climbing (transit time), which may have allowed for some recovery, was not different among trials (p > 0.05). Electromyography median frequency was reduced from beginning to end of each prefatiguing exercise. These results suggest that among the muscle groups studied in men, muscular endurance of DF and EF muscle groups is especially important for rock climbing on 40° overhanging terrain.

Aerobic capacity testing with inactive individuals: the role of subjective experience.

BACKGROUND: Maximal oxygen uptake (VO2max), an assessment of cardiorespiratory fitness, is regularly used as the primary outcome in exercise interventions. Many criteria have been suggested for validating such tests-most commonly, a plateau in oxygen consumption. The current study investigated the proportion of inactive individuals who reached a plateau in oxygen uptake and who achieved a valid test as assessed by secondary criteria (RERmax ≥ 1.1; RPEmax ≥ 18; age predicted HRmax ±10bpm), and the correlates of a successful plateau or achievement of secondary criteria during a VO2max session. METHODS: Participants (n = 240) were inactive individuals who completed VO2max assessments using an incremental treadmill test. We explored physical, behavioral, and motivational factors as predictors of meeting criteria for meeting a valid test. RESULTS: Approximately 59% of the sample achieved plateau using absolute (increase of VO2 of 150ml O2 or less) and 37% achieved plateau using relative (increase of VO2 of 1.5ml/kg O2 or less) criteria. Being male, having a higher BMI, a greater waist-to-hip ratio, and increased self-efficacy were associated with lower odds of achieving an absolute plateau, whereas none of these factors predicted odds of achieving relative plateau. CONCLUSION: Findings raise questions about the validity of commonly used criteria with less active populations.

Palm cooling delays fatigue during high-intensity bench press exercise.

UNLABELLED: Local cooling can induce an ergogenic effect during a short-term intense exercise. One proposed method of personal cooling involves heat extraction from the palm. PURPOSE: In this study, we hypothesized that local palm cooling (PC) during rest intervals between progressive weight training sets will increase total repetitions and exercise volume in resistance-trained subjects exercising in a thermoneutral (TN) environment. METHODS: Sixteen male subjects (mean +/- SD; age = 26 +/- 6 yr, height = 178 +/- 7 cm, body mass = 81.5 +/- 11.3 kg, one-repetition maximum (1RM) bench press = 123.5 +/- 12.6 kg, weight training experience = 10 +/- 6 yr) performed four sets of 85% 1RM bench press exercise to fatigue, with 3-min rest intervals. Exercise trials were performed in a counterbalanced order for 3 d, separated by at least 3 d: TN, palm heating (PH), and PC. Heating and cooling were applied by placing the hand in a device called the rapid thermal exchanger, set to 45 degrees C for heating or 10 degrees C for cooling. This device heats or cools the palm while negative pressure (-35 to -45 mm Hg) is applied around the hand. RESULTS: Total exercise volume during the four PC sets (2480 +/- 636 kg) was significantly higher than that during TN (1972 +/- 632 kg) and PH sets (2156 +/- 668 kg, P < 0.01). The RMS of the surface EMG with PC exercise was higher (P < 0.01), whereas esophageal temperature (P < 0.05) and RPE (P < 0.05) were lower during PC compared with TN and PH. CONCLUSIONS: PC from 35 degrees C to 20 degrees C temporarily overrides fatigue mechanism(s) during intense intermittent resistance exercise. The mechanisms for this ergogenic function remain unknown.

The effect of skin thickness and time in the absorption of dexamethasone in human tendons using iontophoresis.

STUDY DESIGN: Experimental laboratory study. OBJECTIVES: To measure the transmission of dexamethasone sodium phosphate (DEX-P) using iontophoresis as a function of skinfold tissue thickness and time elapsed between treatment and tissue extraction. BACKGROUND: Iontophoresis is a modality used in physical therapy with the intent to drive medications through the skin to underlying tissues using a direct electrical current. DEX-P is the most commonly used medication with iontophoresis and is used to treat a variety of connective tissue conditions. METHODS AND MEASURES: Sixteen adults undergoing anterior cruciate ligament reconstructive surgery using the semitendinosis/gracilis autograft received a 40-mA-min dose of iontophoresis with 0.4% DEX-P superficial to a slip of the distal semitendinosis tendon prior to surgery. The tendon slip was extracted within 4 hours. Time between treatment and tissue extraction and skinfold thickness were measured. Analysis was performed on the slip of the semitendinosis using high-performance liquid chromatography mass spectrum. RESULTS: Of the 16 subjects (10 female, 6 male; mean age, 33 years), 7 had measurable amounts of DEX-P in the tendon slip (4 female, 3 male; mean age, 34 years). The average concentration in the 16 subjects was 2.9 ng/g of tendon tissue. There was no correlation between DEX-P absorbed and skinfold thickness (r = -0.08, P = .79) or time elapsed (r = 0.25, P = .38). In a subset of the 7 individuals that showed measurable levels of DEX-P absorbed, the average concentration of DEX-P was 6.6 ng/g of tendon tissue, and there was a relationship between DEX-P concentrations and time elapsed that did not reach statistical significance (r = 0.71, P = .11). CONCLUSIONS: Iontophoresis appears to facilitate the transmission of dexamethasone to connective tissues in humans with skinfold thickness up to at least 30 mm. The absorption of the dexamethasone seemed to continue to occur for up to 4 hours after delivery. It is not clear why DEX-P was measured in only 7 of the 16 subjects. LEVEL OF EVIDENCE: Therapy, level 5.

Effects of acute leg ischemia during cycling on oxygen and carbon dioxide stores.

This study estimated changes in whole body oxygen stores (O(2)s) and carbon dioxide stores (CO(2)s) during steady state exercise with leg ischemia induced by leg cuff inflation. Six physically fit subjects performed 75 W steady state exercise for 15 min on a cycle ergometer. After 5 min of exercise, cuffs on the upper and lower legs were inflated to 140 mmHg. Cuffs were deflated after 5 min and exercise continued for another 5 min. O(2 )uptake (VO(2)) and CO(2) output (VCO(2)) significantly increased during the first 30 s after inflation, significantly decreased between 60 and 90 s, and then rose linearly until deflation. VO(2) and VCO(2) significantly increased further after cuff deflation, peaking between 30 and 60 s and then returned to near baseline exercise levels. Model-estimated changes in total O(2)s and CO(2)s were compared with time-integrated store changes from VO(2) and VCO(2). During 5 min after cuff deflation, VO(2) and VCO(2) exceeded the model-estimated change in stores by 273 and 697 mL, respectively. These results reflect the O(2) cost repayment of the anaerobic component and lactate buffering to neutralize circulating metabolites caused by the preceding ischemia.

Differential diagnosis of a femoral neck/head stress fracture.

STUDY DESIGN: Resident's case problem. BACKGROUND: Identifying stress fractures of the hip can be a challenging differential diagnosis. Pain presentation is not always predictable and radiographs may not show the fracture, especially during its early stages. Hip stress fractures left untreated can displace and necessitate open reduction internal fixation or total hip arthroplasty. DIAGNOSIS: A 70-year-old woman presented to the physical therapy clinic with complaints of right hip pain. She had been evaluated by a physician and radiographs of the hip, which revealed some arthritic changes, were otherwise normal. Upon examination, the physical therapist observed an antalgic gait, a noncapsular pattern of limitation of hip motion, an empty painful end feel at the end range of motion (ROM) for hip abduction, external rotation, and flexion, and extreme tenderness to palpation over the anterior hip region. The therapist suspected a more pernicious problem than osteoarthritis and discussed his suspicion with the physician. The physician subsequently requested an MRI that revealed a femoral neck and head stress fracture that was later confirmed with a bone scan. The patient was provided with a walker for ambulation with a non-weight-bearing status for 6 weeks, after which she returned to physical therapy for progressive weight bearing and strengthening. She was discharged with a relatively pain-free hip and was ambulating with a cane. A 2-month follow-up examination revealed a pain-free hip and a return to all premorbid activities, including ambulation without an assistive device. DISCUSSION: The presence of a normal radiograph of the hip should not be considered conclusive in ruling out a stress fracture in the hip region. The current case demonstrates how careful evaluation can reveal occult pathologies and prevent potentially catastrophic morbidity.

Effects of ischemic training on leg exercise endurance.

This study tested whether ischemic exercise training (Tr(IS+EX)) would increase endurance of ischemic (Ex(IS)) and ramp exercise (Ex(RA)) knee-extension tests more than exercise training (Tr(EX)) alone. Ten healthy subjects performed pre- and posttraining tests with each leg. For Ex(RA), after subjects warmed up, a weight was added each minute until they were exhausted. Ex(IS) was similar, but after warm-up, we inflated a thigh cuff to 150 mmHg instead of adding weights. One leg was chosen for Tr(IS+EX) (cuff inflated to 150 mmHg during exercise) and the other for Tr(EX), both with a small weight on each leg, four to six times per daily session for 3 to 5 min each, 5 days per week for 6 weeks. Ex(IS) duration increased 120% more (p = 0.002) in the Tr(IS+EX) leg than in the contralateral Tr(EX) leg, whereas Ex(RA) duration increased only 16% (nonsignificant). Tr(IS+EX )and Tr(EX) significantly attenuated the ventilation increase (ergoreflex) during Ex(IS). TheO(2) debt for Ex(IS )was significantly lower and systolic blood pressure recovery was faster after Tr(IS+EX) than after Tr(EX). Heart rate recovery after Ex(RA )andEx(IS )was faster after Tr(IS+EX). Apparently, Tr(IS+EX) with low-intensity resistance increases exercise endurance and attenuates the ergoreflex and therefore may be a useful tool to increase regional muscle endurance to improve systemic exercise capacity in patients.

Leg length discrepancy.

The role of leg length discrepancy (LLD) both as a biomechanical impediment and a predisposing factor for associated musculoskeletal disorders has been a source of controversy for some time. LLD has been implicated in affecting gait and running mechanics and economy, standing posture, postural sway, as well as increased incidence of scoliosis, low back pain, osteoarthritis of the hip and spine, aseptic loosening of hip prosthesis, and lower extremity stress fractures. Authors disagree on the extent (if any) to which LLD causes these problems, and what magnitude of LLD is necessary to generate these problems. This paper represents an overview of the classification and etiology of LLD, the controversy of several measurement and treatment protocols, and a consolidation of research addressing the role of LLD on standing posture, standing balance, gait, running, and various pathological conditions. Finally, this paper will attempt to generalize findings regarding indications of treatment for specific populations.

Keyboarding and visual-motor skills in elementary students: a pilot study.

UNLABELLED: With the increased integration of technology in public school settings, occupational therapists have utilized computers in their role as related special education service providers. Although computers are used as an intervention tool, no studies have documented the efficacy of computer training on functional skills in students. PURPOSE: The purpose of this pilot study was to investigate the effect of a structured keyboarding (typing) program on visual-motor (eye-hand coordination) and written communication skills in children enrolled in second grade public school classrooms. METHOD: Sixty-six children participated in the study. Thirty-two children received typing instruction on a daily basis for eight months and thirty-four students served as control children receiving no formal instruction. RESULTS: RESULTS of a mixed ANOVA with repeated factor showed a significant difference in visual-motor abilities in students who received keyboarding instruction as compared to control children. In addition, average typing speeds approached handwriting speeds at this grade level. These preliminary results support the use of keyboarding as a compensatory handwriting approach in the classroom. Further investigation of the use of keyboarding for students with milder disorders such as learning disabilities is recommended.