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Twice-weekly evoked RT to the paralyzed lower extremities resulted in significant skeletal muscle hypertrophy that was associated with reduction in VAT, VAT/subcutaneous adipose tissue ratio, and percent IMF. Significant improvements in insulin profile and lipid metabolism were noted in the RT + diet when compared with diet alone.

Several body composition and metabolic-associated disorders such as glucose intolerance, insulin resistance, and lipid abnormalities occur prematurely after spinal cord injury (SCI) and at a higher prevalence compared to able-bodied populations. Within a few weeks to months of the injury, there is a significant decrease in total lean mass, particularly lower extremity muscle mass and an accompanying increase in fat mass. The infiltration of fat in intramuscular and visceral sites is associated with abnormal metabolic profiles. The current review will summarize the major changes in body composition and metabolic profiles that can lead to comorbidities such as type 2 diabetes mellitus and cardiovascular diseases after SCI. It is crucial for healthcare specialists to be aware of the magnitude of these changes. Such awareness may lead to earlier recognition and treatment of metabolic abnormalities that may reduce the co-morbidities seen over the lifetime of persons living with SCI.

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This study examined the relationship among regional and relative adipose tissue distribution, glucose, and lipid metabolism in men with spinal cord injury (SCI). After overnight fasting, 32 individuals with motor complete tetraplegia (Tetra) (n = 7) and paraplegia (Para) (n = 25) underwent resting energy expenditure and measurement of serum lipid profile, followed by an oral glucose tolerance test to measure plasma glucose and plasma insulin concentrations. Regional fat mass (FM) and fat-free mass were quantified using dual-energy X-ray absorptiometry. Relative adipose tissue was calculated as the ratio of leg FM/trunk FM, leg FM/whole-body FM, and trunk FM/whole-body FM. Individuals with Tetra have greater leg FM/trunk FM (45%) and leg FM/body FM (26%) and lower trunk FM/body FM (29%) ratios than individuals with Para (p < 0.05). Glucose area under the curve (AUC) was positively related to leg FM (r = 0.34, p = 0.05) but not to trunk or body FM. Strong negative relationships were noted between the ratio of trunk FM to body FM and glucose AUC (r = -0.38, p = 0.03) and low-density lipoprotein cholesterol (LDL-C) (r = -0.45, p = 0.001). Whole-body FM was negatively related to high-density lipoprotein cholesterol (r = -0.49, p = 0.007) after controlling for percentage of trunk FM. Both leg and trunk FM may play a pivotal role in determining the metabolic profile in individuals with SCI. Relative to whole-body FM and leg FM, trunk FM may induce a protective effect on glucose homeostasis and the LDL-C profile.

This study examined the eVects of altering surface neuromuscular electrical stimulation (SNMES) parameters on the speciWc tension of the quadriceps femoris muscle. Seven able-bodied subjects had magnetic resonance images taken of both thighs prior to and immediately after four SNMES protocols to determine the activated muscle cross-sectional area (CSA). The four protocols were: (1) research (RES, 100 Hz, 450 s, and amplitude set to evoke 75% of maximal voluntary isometric torque, MVIT); (2) pulse duration (PD, 100 Hz, 150 s, same current as in RES); (3) frequency (FREQ, 25 Hz, 450 s, and same current as in RES); (4) amplitude (AMP, 100 Hz, 450 s, and current set to evoke the average of the initial torques of PD and FREQ, 45 § 9% of MVIT). Reducing the amplitude of the current from 75 to 45% of MVIT did not alter speciWc tension, 25 § 8 N/cm 2 , suggesting that the amplitude probably aVects torque and the area of activated muscle proportionally. Shortening the pulse duration from 450 to 150 s caused speciWc tension to drop from 25 § 6 to 20 § 6 N/cm 2 (P < 0.05), indicating that pulse duration increased torque and the activated CSA disproportionally. Alternatively, reducing the frequency from 100 to 25 Hz decreased speciWc tension from 25 § 6 to 17 § 4 N/cm 2 (P < 0.05), suggesting that the frequency increased torque without aVecting the activated CSA. Clinicians who administer SNMES should be aware of the magnitude of adaptations to a given amplitude, pulse duration, and frequency.

N euromuscular electrical stimulation (NMES) is a promising tool in the rehabilitation of individuals with a limited ability to activate their skeletal muscles, 13,35,36 as well as a method of strength training and short-term resistance training in athletic populations. 26,27 During NMES application, the capacity to maintain performance is compromised compared to voluntary exercise, Experimental laboratory study.The primary purpose was to investigate the independent effects of current amplitude, pulse duration, and current frequency on muscle fatigue during neuromuscular electrical stimulation (NMES). A second purpose was to determine if the ratio of the evoked torque to the activated area could explain muscle fatigue.Parameters of NMES have been shown to differently affect the evoked torque and the activated area. The efficacy of NMES is limited by the rapid onset of muscle fatigue.Seven healthy participants underwent 4 NMES protocols that were randomly applied to the knee extensor muscle group. The NMES protocols were as follows: standard protocol (Std), defined as 100-Hz, 450-μs pulses and amplitude set to evoke 75% of maximal voluntary isometric torque (MVIT); short pulse duration protocol (SP), defined as 100-Hz, 150-μs pulses and amplitude set to evoke 75% of MVIT; low-frequency protocol (LF), defined as 25-Hz, 450-μs pulses and amplitude set to evoke 75% of MVIT; and low-amplitude protocol (LA), defined as 100-Hz, 450-μs pulses and amplitude set to evoke 45% of MVIT. The peak torque was measured at the start and at the end of the 4 protocols, and percent fatigue was calculated. The outcomes of the 4 NMES protocols on the initial peak torque and activated cross-sectional area were recalculated from a companion study to measure torque per active area.Decreasing frequency from 100 to 25 Hz decreased fatigue from 76% to 39%. Decreasing the amplitude and pulse duration resulted in no change of muscle fatigue. Torque per active area accounted for 57% of the variability in percent fatigue between Std and LF protocols.Altering the amplitude of the current and pulse duration does not appear to influence the percent fatigue in NMES. Lowering the stimulation frequency results in less fatigue, by possibly reducing the evoked torque relative to the activated muscle area.

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