Reliability of Gallon-Jug Shelf-Transfer Power Equations in Older Women.

ABSTRACT: Ly, A, Strand, KL, Courtney, KJ, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Reliability of gallon-jug shelf-transfer test power equations in older women. J Strength Cond Res 37(5): 1124-1130, 2023-This study examined the test-retest reliability of the gallon-jug shelf-transfer (GJST) test as a measure of upper-body functional power in older women. Although the validity of the predictive equations for power during the GJST test has been established, for the test to be viable in either a laboratory or clinical environment, between-day and within-day reliability must be established. Thirty-four independently living older women (mean ± SD : 75.0 ± 6.4 years) performed 2 sets of 3 repetitions of the GJST test on 2 days separated by at least 48 hours. Using the established predictive equations, the values for peak power and average power were then computed. Statistical analyses to assess reliability included intraclass correlation coefficient, coefficient of variation (CV), SEM , minimal detectable change (MDC), and Cronbach's α values. Furthermore, Bland-Altman plots evaluated the agreement between the tests. Intraclass correlation coefficient (>0.91, p < 0 001), CV (<8.1%), SEM (<5.94 W), MDC (<14 W), and Cronbach's α (>0.95) indicated excellent reliability. The lines of equality for all Bland-Altman plots fell within the 95% confidence interval of the mean difference, implying that there were no significant differences between tests. Furthermore, bias values were small (<11.15 W), and the limits of agreement (LOA) were within an acceptable range. Based on our statistical analyses, the GJST test is a highly reliable assessment for determining object transfer power for healthy older women.

Validity and Reliability of the Seated Medicine Ball Throw as a Measure of Upper Body Power in Older Women.

ABSTRACT: Strand, KL, Ly, AS, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Validity and reliability of the seated medicine ball throw as a measure of upper body power in older women. J Strength Cond Res 37(4): 902-908, 2023-In women, aging is associated with diminishing upper body power, which may increase the risk of falls and fall-related injury; however, the validity and reliability of clinical tests to evaluate upper body power need to be confirmed. The seated medicine ball throw (SMBT) is an upper body performance test used to monitor muscle function among older individuals. The purpose of this study was to evaluate the validity and test-retest reliability of the SMBT in older women. Thirty-five women (age = 75.15 ± 6.39 years) participated in this study. Subjects performed SMBT trials using common ball masses (SMBT 4lb and SMBT 3kg ) over 3 sessions. Familiarization with the SMBT and chest press 1 repetition maximum (CP 1RM ) was provided on the first day. On day 2, subjects repeated the tests, but data were recorded. On day 3, SMBT was retested followed by an evaluation of chest press peak power (CP PP ) values at 30-80% of CP 1RM . Significant correlations ( p ≤ 0.05) were found between the CP PP and SMBT 4lb ( r = 0.775, p < 0.001) and SMBT 3kg ( r = 0.734, p < 0.001), and SMBT distance showed expected declines with age ( r = -0.724 to -0.626, p < 0.001), demonstrating its validity. High reliability between testing days was found, and Bland-Altman plots showed few points that fell outside the limits of agreement. In conclusion, the SMBT is a valid and highly reliable tool that can be used by health professionals to monitor deficits in upper body muscular power to improve treatment protocols in older women.

Association Between Neuromuscular Variables and Graft Harvest in Soft Tissue Quadriceps Tendon Versus Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Autografts.

BACKGROUND: Quadriceps tendon (QT) autografts are increasingly popular for anterior cruciate ligament reconstruction (ACLR). However, no study has compared QT autografts with bone-patellar tendon-bone (BTB) autografts regarding the electromechanical delay (EMD), the peak torque (PT), and the rate of force development (RFD) in the superficial quadriceps muscles (rectus femoris [RF], vastus medialis [VM], and vastus lateralis [VL]). HYPOTHESES: We hypothesized (1) there would be a significantly lower PT, lower RFD, and longer quadriceps EMD of the operative limb for the QT versus the BTB autograft; (2) the PT, the RFD, and the quadriceps EMD of the operative limb would be significantly depressed compared with those of the nonoperative limb, regardless of the surgical technique; and (3) there would be greater increases in the RF EMD than in the VM or the VL EMD. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 34 patients (age, 18-40 years), who had undergone ACLR (QT, n = 17; BTB, n = 17) at least 1 year before testing and performed 3 perceived maximal effort isometric tests, which were time synchronized with surface electromyography (EMG) on their operative and nonoperative limbs, were included in this study. EMD, PT, and RFD data were analyzed using a 2 (limb) × 2 (graft) × 3 (repetition) mixed repeated-measures analysis of variance. RESULTS: The EMD, the PT, and the RFD were not significantly affected by graft choice. For the VL, a significant repetition × graft × limb interaction was detected for the VL EMD (P = .027; ηp = 0.075), with repetition 3 having longer EMD than repetition 2 (mean difference [MD], 16 milliseconds; P = .039). For the RF EMD, there was a significant repetition × limb interaction (P = .027; ηp = 0.074), with repetition 3 being significantly longer on the operative versus the nonoperative limb (MD, 24 milliseconds; P = .004). Further, the operative limb EMD was significantly longer for repetition 3 versus repetition 2 (MD, 17 milliseconds; P = .042). For the PT, there was a significant effect for repetition (P = .003; ηp = 0.114), with repetition 1 being significantly higher than both repetitions 2 (MD, 8.52 N·m; P = .001) and 3 (MD, 7.79 N·m; P = .031). For the RFD, significant limb (P = .034; ηp = 0.092) and repetition (P = .010; ηp = 0.093) effects were seen, with the nonoperative limb being significantly faster than the operative limb (MD, 23.7 N·m/s; P = .034) and repetition 1 being significantly slower than repetitions 2 (MD, -20.46 N·m/s; P = .039) or 3 (MD, -29.85 N·m/s; P = .002). CONCLUSION: The EMD, the PT, and the RFD were not significantly affected by graft type when comparing QT and BTB autografts for ACLR; however, all neuromuscular variables were affected regardless of the QT or the BTB harvest.

Leg press and chest press strength normative values by half-decades in older persons.

Evaluating muscular strength is vital to the application of effective training protocols that target quality of life and independence in older individuals. Resistance training is a valuable tool to improve functional capacity, strength, and power in this population; however, the lack of normative values for common lifts such as the leg press (LP) and chest press (CP) reduce its utility. This study developed age- and sex-specific normative strength values for older individuals. LP and CP 1-repetition maximum (1RM) values on Keiser A420 pneumatic machines were compiled from 445 older adults, ages 60-85y. Descriptive statistics and quartile rankings are reported, and two-way ANOVAs were conducted to determine differences between sex and age groups. There were significant sex x age group interactions for LP and CP. Men were significantly stronger than women across all age groups for both exercises (p < .01); however, the mean difference decreased with age. For men, no differences were seen among the 60-64 (237 ± 39 kg), 65-69 (223 ± 43 kg) and 70-74 (219 ± 50 kg) age groups; but the 60-64 group showed higher strength values than the 75-79 group (193 ± 52 kg) and all three groups contained higher strength values than the 80-85 group (172 ± 40 kg). Similarly, for relative strength, the 60-64 group (2.80 ± 0.53 kg·kgBM) surpassed values for all groups but the 65-69, and the 65-69 (2.70 ± 0.54 kg·kgBM) produced greater strength values than the 70-74 (2.45 ± 0.47 kg·kgBM), 75-79 (2.09 ± 0.37 kg·kgBM) and 80-85 (2.19 ± 0.38 kg·kgBM) groups. In contrast, no significant differences in absolute or relative strength were seen among age groups for the women. Our study establishes absolute and relative age- and sex-specific normative values for the LP1RM and CP1RM in older individuals. These values allow practitioners and researchers to interpret the results of various interventions, and evaluate their importance to evaluation of sarcopenia, injury risk, functional mobility and quality of life. Additionally, our results reveal that age-related declines in strength are prominent for male LP and CP, but not female CP or LP.

Periodized Resistance Training With and Without Functional Training Improves Functional Capacity, Balance, and Strength in Parkinson's Disease.

ABSTRACT: Strand, KL, Cherup, NP, Totillo, MC, Castillo, DC, Gabor, NJ, and Signorile, JF. Periodized resistance training with and without functional training improves functional capacity, balance, and strength in Parkinson's disease. J Strength Cond Res 35(6): 1611-1619, 2021-Periodized progressive resistance training (PRT) is a common method used to improve strength in persons with Parkinson's disease (PD). Many researchers advocate the addition of functional training to optimize translation to activities of daily living; however, machine-based PRT, using both force and velocity training components, may elicit similar benefits. Thirty-five persons with PD (Hoehn and Yahr I-III) were randomized into a strength, power, and hypertrophy (SPH; n = 17) or strength, power, and functional (SP + Func; n = 18) group, training 3 times weekly for 12 weeks. Both groups performed machine-based strength and power training on days 1 and 2 each week, respectively; whereas, on day 3, SPH group performed machine-based hypertrophy training and SP + Func group performed functional training. Functional performance was tested using the timed up and go, 30-second sit-to-stand (30-s STS), gallon-jug shelf-transfer, and seated medicine ball throw (SMBT) tests. Balance (Mini-BESTest), strength, motor symptoms (UPDRS-III), quality of life, and freezing of gait (FOG) were also assessed. Repeated measures analysis of variance revealed a main effect for time (p ≤ 0.05) with significant improvements for the sample in the 30-s STS (p = 0.002), SMBT (p = 0.003), Mini-BESTest (p < 0.001), upper-body strength (p = 0.002) and lower-body strength (p < 0.001). A significant group × time interaction was seen for FOG, with SP + Func alone showing improvement (p = 0.04). Furthermore, the SPH group produced a clinically important difference for the UPDRS-III (mean difference = 4.39, p = 0.18). We conclude that both exercise strategies can be equally effective at improving functional capacity, balance, and muscular strength in individuals with PD. In addition, FOG and motor symptoms may be targeted through SP + Func and SPH, respectively. The results provide options for individualized exercise prescriptions.

One Repetition Maximum Test-Retest Reliability and Safety Using Keiser Pneumatic Resistance Training Machines With Older Women.

ABSTRACT: Infante, MA, Harrell, GM, Strand, KL, Parrino, RL, and Signorile, JF. One repetition maximum test-retest reliability and safety using Keiser pneumatic resistance training machines with older women. J Strength Cond Res 35(12): 3513-3517, 2021-Chest press (CP) and leg press (LP) are the most common exercises used to assess strength in older persons; therefore, the reliability of these tests is critical to clinicians and researchers. Because women comprise the highest proportion of the older population, this study examined the test-retest reliability of Keiser A420 pneumatic machines during CP and LP 1 repetition maximum (1RM) testing in 23 older women on 2 separate occasions, trial 1 (T1) and trial 2 (T2), at least 72 hours apart. Significance was set at <0.05. CP1RM and LP1RM showed excellent test-retest reliability (intraclass correlation coefficient = 0.974, 0.972, respectively, p < 0.001) and low coefficients of variation (CP1RM = 5.28%; LP1RM = 6.32%). Standard error of measurement for CP1RM (0.97 kg) was lower than that of LP1RM (6.36 kg). The minimal detectable change (MDC) for the CP1RM and LP1RM was 2.69 and 17.63 kg, respectively. Bland-Altman plots revealed only 1 point outside of the 95% CI for comparison of T1 and T2 for either exercise, there was little systematic error across average values, both lines of equality fell within the limits of agreement (LOA), and the bias between T1 and T2 for both exercises was below 5% of the average 1RM. By contrast, the LOA for CP1RM and LP1RM are somewhat wide because they both exceeded their computed MDC values. Given the excellent test-retest reliability of the Keiser A420 pneumatic CP and LP machines with older women, clinicians and researchers can confidently and safely use these machines for 1RM testing after proper familiarization.

Yoga Meditation Enhances Proprioception and Balance in Individuals Diagnosed With Parkinson's Disease.

This study compared the effectiveness of two proprioceptive exercise programs for persons diagnosed with Parkinson's disease (PD). Thirty-three patients with mild to moderate PD were randomly assigned to a yoga meditation program (YoMed) or to an established proprioceptive training program (PRO). Both interventions included twice weekly sessions (45 minutes each), spanning a 12-week period. Outcome measures included: joint position sense (JPS45°, JPS55°, JPS65°) and joint kinesthesia (JKFlex and JKExt), the Tinetti Balance Assessment Tool (TIN), Falls Efficacy Scale (FES), Balance Error Scoring System (BESS), dynamic posturography (DMA and TIME) and the Timed Up-and-Go Test (TUG). Test administrators were blinded to group affiliation. Significant between-group differences favoring the YoMed group were observed for TIN (p = 0.01, d = 0.77) and JKFlex (p = 0.05, d = -0.72). DMA and TIME scores significantly improved for both groups, and no adverse events were reported. These findings indicate that the YoMed program is safe and effective for patients with PD. Researchers should continue to examine the clinical efficacy of mind-body techniques to improve movement control and body awareness in this population.

The Development of a Regression Model to Predict Object Transfer Power in Older Adults.

Castillo, DC, Strand, KL, Oh, J, Eltoukhy, M, Totillo, MC, and Signorile, JF. The development of a regression model to predict object transfer power in older adults. J Strength Cond Res 34(11): 3086-3093, 2020-Declines in mechanical power affect independence in older adults; however, no practical clinical method exists to assess peak power (PP) and average power (AP) during transfer tasks in this population. Therefore, predictive models were developed and validated during performance of an existing transfer assessment, the gallon-jug shelf-transfer (GJST) test. Twenty-one independent-living older women (age = 74.8 ± 5.6) and men (age = 73.8 ± 4.5) participated in the development phase. Peak power and AP were computed using data from three-dimensional movement analyses while subjects moved five 1-gallon jugs from a low (0.59 m) to high shelf (1.43 m) as quickly as possible. Stepwise linear regression models using test duration, subject height, and age produced equations with high R values for PP (0.655-0.701; p < 0.0001) and AP (0.703-0.759; p < 0.0001). However, regression and Bland-Altman analyses showed models with declining agreement as power values increased. Therefore, analyses were repeated using a quadratic model, showing stronger predictive capacity (PP: R = 0.786; AP: R = 0.878; p < 0.0001). Validity of this model was evaluated in a second sample of 30 older women (age = 69.9 ± 4.7) and men (age = 70.7 ± 4.3). Computed GJST AP and PP were compared with power produced during dominant arm chest press and distance during the seated medicine ball throw. Generalizability of these models was also confirmed through cross-validation analyses. Our results indicate mechanical power in older adults can be accurately measured using the quadratic model, with test duration as the independent variable. This model provides a simple, safe, and inexpensive assessment tool that can be administered by clinicians to improve diagnostic and therapeutic processes in older persons.

Power vs strength training to improve muscular strength, power, balance and functional movement in individuals diagnosed with Parkinson's disease.

BACKGROUND: Declines in strength and power are cardinal symptoms of Parkinson's disease (PD), a progressive neuromuscular disorder. Progressive resistance training (PRT) has been shown to reduce a wide variety of PD-related motor deficits; however, no study has examined differences between the two most common RT methodologies utilized in this population, high-load, low velocity strength training (ST) and low-load, high-velocity power training (PT). The primary purpose of this study was to compare the effects of ST and PT on measures of strength, power, balance and functional movement in persons with PD. METHOD: Thirty-five persons with mild to moderate PD (Hoehm and Yahr Stages = 1-3; UPDRS Part III = 30.6 ±â€¯14.0) were randomized into either a ST or PT group involving 12 weeks of supervised PRT (2 visits per week). Leg press (LP) and chest press (CP) muscular strength (1RM) and muscular peak power (PP) were assessed before and after the twelve week training period as primary outcome measures. In addition, secondary measures of balance (Berg Balance Assessment (BBA), dynamic posturography (DMA), Modified Falls Efficacy Scale (MFES)), functional movement (timed up-and-go), and quality of life (PDQ-39 summary index and Mobility subscore) were obtained at the same time points, given the impact of PD symptoms on fall probability and independence. RESULTS: Repeated measures ANCOVA revealed significant improvements in LP 1RM (Mdiff = 54.89 kg, 95% CI: 43.38, 66.40; p < .05; d = 3.38) and CP 1RM (Mdiff = 7.33 kg, 95% CI: 4.75, 9.91; p < .05; d = 2.02). Additionally, significant improvements were seen in LPPP (Mdiff = 112.27 W, 95% CI: 56.03, 168.51; p < .05; d = 1.42) and CPPP (Mdiff = 52.1 W, 95% CI: 23.38, 80.86; p = .001; d = 1.29). No significant improvements were seen for any secondary outcome measures, however BBA scores were shown to significantly decrease following the intervention (Mdiff = -1.686, 95% CI: -2.89, -0.482; p = .007 d = -0.96), although this change did not reach clinical significance (clinically meaningful change = ±4.0). In addition, the ST group demonstrated significantly poorer PDQ-39SI scores (Mdiff = 4.96, 95% CI: 0.54, 9.38; p = .029), whereas the entire sample showed significantly poorer PDQ-39MOB scores (Mdiff = 4.80, 95% CI: 0.17, 9.43; p = .043; d = 0.71). CONCLUSIONS: Both ST and PT appear to be effective at reducing the neuromuscular deficits associated with PD; however, the use of these interventions for improving functional performance was not supported.

Optimal loads for power in older men and women using plate-loaded resistance machines.

BACKGROUND: Age-related decrements in power affect quality of life in older adults; however, no studies have determined the optimal loads that maximize power outputs using the most commonly employed lifting equipment, plate-loaded machines. METHODS: Fifteen older men (69.2 ±â€¯6.9 y) and 22 older women (68.9 ±â€¯5.9 y) performed two sessions of strength and power testing. Individuals completed ten plate-loaded exercises to determine their maximum dynamic strengths (1RM) and peak power outputs (PP). Power was tested at 40, 50, 60, 70 and 80% 1RM using a linear position transducer. PP was expressed relative to the highest power produced (PPREL). RESULTS: Multi-joint exercises produced optimal load values at 50-60%1RM for leg press, 50%1RM for chest press, and 40-60%1RM for seated row, with no significant differences among loads for shoulder press. Single-joint exercise optimal loads were seen at 50-60% for hip adduction, 50-70%1RM for calf raise, 60-80%1RM for biceps curl, and 50-80%1RM for triceps extension, with no significant differences between loads for hip abduction or leg curl. No significant differences were found between sexes for any exercise. CONCLUSIONS: Different optimal load ranges are required for individual plate-loaded exercises in older persons. Specifically, multi-joint exercises demonstrated a narrow optimal load range favoring the velocity end of the load-velocity curve, while single-joint exercises produced a wider optimal load range extending into the upper limits of the load end of the curve.

Optimal Approach to Load Progressions during Strength Training in Older Adults.

Progressive resistance training (RT) is one of the most effective interventions for reducing age-related deficits in muscle mass and functional capacity. PURPOSE: To compare four approaches to load progressions in RT for older adults to determine if an optimal method exists. METHODS: Eighty-two healthy community-dwelling older adults (71.8 ± 6.2 yr) performed 11 wk of structured RT (2.5 d·wk) in treatment groups differing only by the method used to increase training loads. These included percent one repetition maximum (%1RM): standardized loads based on a percentage of the one repetition maximum (1RM); rating of perceived exertion (RPE): loads increased when perceived difficulty falls below 8/10 on the OMNI-Resistance Exercise Scale perceived exertion scale; repetition maximum (RM): loads increased when a target number of repetitions can be completed with a given load; repetitions in reserve (RiR): identical to RM except subjects must always maintain ≥1 "repetition in reserve," thus avoiding the possibility of training to temporary muscular failure. RESULTS: Multiple analyses of covariance indicated no significant between-group differences on any strength (chest press 1RM; leg press 1RM) or functional performance outcome (usual walking speed, maximum walking speed, 8-ft timed up-and-go, gallon jug transfer test, 30 s sit-to-stand). The RPE group found the exercise to be significantly more tolerable and enjoyable than subjects in the RiR, RM, and %1RM groups. CONCLUSION: Given the RM, RPE, %1RM, and RiR methods appear equally effective at improving muscular strength and functional performance in an older population, we conclude that the RPE method is optimal because it is likely to be perceived as the most tolerable and enjoyable, which are two important factors determining older adults' continued participation in RT.