Effect of an Herbal/Botanical Supplement on Recovery from Delayed Onset Muscle Soreness: A Randomized Placebo Controlled Trial

Background: We examined the effects of a proprietary herbal/botanical supplement (StemSport, Stemtech, San Clemente, CA.) suggested to increase circulating stem cells, decrease inflammation, and attenuate exercise induced muscle damage on recovery from delayed onset muscle soreness (DOMS). Methods: Sixteen subjects (male = 7, female = 9; age 23.8 ± 10 years; height 171.9 ± 10 cm, mass 72.2 ± 15 kg) were randomized in a crossover, double-blind, placebo controlled trial to receive a placebo or StemSport supplement (6150 mg/day) for 14 days. DOMS was induced on day 7 for both placebo and active conditions in the non-dominant elbow flexor group with repeated eccentric repetitions. Muscle swelling (biceps girth), elbow flexor isometric strength (hand held dynamometer), muscle pain/tenderness (visual analog scale), range of motion (active elbow flexion and extension), and inflammation (hsCRP, IL6, and TNF-ɑ) were measured at baseline and at 24 h, 48 h, 72 h, and 168 h (1 week) post eccentric exercise. The crossover washout period was \u3e= 14 days. Results: No significant condition-by-time interactions between placebo and StemSport supplementation were observed with regard to measures of pain (p = 0.59), tenderness (p = 0.71), isometric strength (p = 0.32), elbow flexion (p = 0.45), muscle swelling (p = 0.90), or inflammation (p \u3e 0.90). Decrements in elbow extension range of motion 48 h post-exercise were less after StemSport supplementation (Δ elbow extension 48 h post; StemSport, -2.0 deg; placebo, -10 deg; p = 0.003). Conclusions: These data suggest that compared to placebo, StemSport supplementation does not improve outcome measures related to muscle recovery after acute upper-arm induced DOMS

Validity of the relative percent concept for equating training intensity

The validity of the relative percent concept for equating training intensity was investigated using the point of metabolic acidosis (anaerobic threshold) as the criterion variable. Percent oxygen uptake, heart rate and metabolic acidosis were determined at 60, 70, and 80% of max heart rate on a bicycle ergometer test ( N =31). At 60 and 70% of max heart rate only one individual was definitely in metabolic acidosis. At 80% max heart rate 17 subjects were working at a level above the point of metabolic acidosis while 14 were working at or below this point. Thus, it was suggested that even if subjects are exercising at the same relative percent maximum HR, the metabolic stress using metabolic acidosis as the criterion is not constant across subjects. It was further shown that the regression of percent O 2 max on percent max HR was a spurious one resulting in poor prediction of individual O 2 values. The data presented suggest that the relative percent concept for equating exercise or subsequent training intensity needs careful re-evaluation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47421/1/421_2004_Article_BF00421445.pd

Effect of an herbal/botanical supplement on strength, balance, and muscle function following 12-weeks of resistance training: a placebo controlled study

Background: StemSport (SS; StemTech International, Inc. San Clemente, CA) contains a proprietary blend of the botanical Aphanizomenon flos-aquae and several herbal antioxidant and anti-inflammatory substances. SS has been purported to accelerate tissue repair and restore muscle function following resistance exercise. Here, we examine the effects of SS supplementation on strength adaptations resulting from a 12-week resistance training program in healthy young adults. Methods: Twenty-four young adults (16 males, 8 females, mean age = 20.5 ± 1.9 years, mass = 70.9 ± 11.9 kg, stature = 176.6 ± 9.9 cm) completed the twelve week training program. The study design was a double-blind, placebo controlled parallel group trial. Subjects either received placebo or StemSport supplement (SS; mg/day) during the training. 1-RM bench press, 1-RM leg press, vertical jump height, balance (star excursion and center of mass excursion), isokinetic strength (elbow and knee flexion/extension) and perception of recovery were measured at baseline and following the 12-week training intervention. Results: Resistance training increased 1-RM strength (p \u3c 0.008), vertical jump height (p \u3c 0.03), and isokinetic strength (p \u3c 0.05) in both SS and placebo groups. No significant group-by-time interactions were observed (all p-values \u3e0.10). Conclusions: These data suggest that compared to placebo, the SS herbal/botanical supplement did not enhance training induced adaptations to strength, balance, and muscle function above strength training alone

Pre-synaptic modulation of quadriceps arthrogenic muscle inhibition

Arthrogenic muscle inhibition (AMI) impedes rehabilitation following knee joint injury by preventing activation of the quadriceps. AMI has been attributed to neuronal reflex activity in which altered afferent input originating from the injured joint results in a diminished efferent motor drive to the quadriceps muscles. Beginning to understand the mechanisms responsible for muscle inhibition following joint injury is vital to control or eliminate this phenomenon. Therefore, the purpose of this investigation is to determine if quadriceps AMI is mediated by a presynaptic regulatory mechanism. Eight adults participated in two sessions: in one session their knee was injected with saline and in the other session it was not. The maximum Hoffmann reflex (H-reflex), M-wave, reflex activation history, plasma epinephrine, and norepinephrine were recorded at: baseline, post needle stick, post lidocaine, and 25 and 45 min post effusion. Measures for the control condition were matched to the effusion condition. The percent of the unconditioned reflex amplitude for reflex activation history and the maximum H-reflex were decreased at 25 and 45 min post effusion as compared to measures taken at baseline, post needle stick, and post lidocaine ( P 0.05). No differences were detected at any time interval for any measure during the control admission ( P >0.05). Quadriceps AMI elicited via an experimental knee joint effusion is, at least in part, mediated by a presynaptic mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46099/1/167_2004_Article_547.pd

Oxygen Transport As The Major Limiting Factor In Aerobic Endurance Performance.

PhDPhysical educationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/189475/2/7627613.pd

Predictability of Body Segment Volumes in Living Subjects

The validity of the “segment-zone” anthropometric method for calculat­ing segmental volume was studied for the limbs, and head and neck in 23 female (mean age, 21 yr; mean weight, 54 kg) and 24 male (mean age, 21 yr; mean weight, 76 kg) subjects. The arms and forearms were viewed as a series of 3 truncated cones, thighs and legs a series of 4 truncated cones, hands and feet as wedges, head as a sphere, and neck as 1 truncated cone. The necessary girths and zone heights were obtained for each zone for use in calculating the respective zone volumes using appropriate geometric formulae. The validity of this technique was computed as the correlations between the calculated segmental volume versus the segment volume obtained by water displacement (criterion volume). All the validity coefficients were significant at the .01 level, except for the head and neck for males and females and right and left foot for females. In addition, the only significant difference found between the mean calculated and the mean criterion segment volumes were for the hands and feet and head and neck for both males and females. Multiple linear regression equations were computed using the anthropometric data to predict the criterion segmental volumes. The validity of these equations was reported for a separate sample of subjects

Predicting Body Composition of Men from Girth Measurements

The purpose of this study was to develop regression equations for predicting density and % body fat. Subjects, 532 males, were hydro- statically weighed, and circumference measurement recorded for thigh, hips (buttocks), iliac, abdomen, and chest. Age (range = 21 to 78 yrs), weight (56.2 to 152.8 kg), and height (146.1 to 193.0 cm) were also recorded. Percent body fat ranged from 2.0 to 48.8%. Step-wise multiple regression was used to select the best set of predictors of body density and % of body fat from the eight independent (predictor) measures. Capitalization on chance was negligible due to the favorable subject to predictor ratio (58 subjects per predictor). The regression equation (N = 462) developed for predicting % body fat was: % body fat = —47.371817 + (0.57914807 x abdomen) + (0.25189114 x hips) + (0.21366088 x iliac) — (0.35595404 x weight)[S.E.E. = 3.6, R = .839, R2adj = .702] Using the above equation on a cross-validation sample (N = 70) produced a predicted mean (±SD) of 25.6 ± 6.6% (validation sample mean = 26.0 ±6.6%) and a total error (S.E.) of 4-4%. The use of three girth measurements and total body weight enabled us to develop equations for predicting body density and % body fat that are comparable in accuracy to skinfold calipers and should provide a viable alternative to skinfold measurements

A Non Population-Specific Method for Predicting Total Body Volume and Percent Fat

The validation of the segment zone approach as a non population-specific method for predicting total body volume and percent fat was investigated.The regression equation generated on 24 college-aged women, in a previous study, was validated on 47 prepubescent children, 22 college-aged men, 242 college-aged women, 84 middle-aged men and 60 middle-aged women. Segment zone girth measures were determined for all subjects. Criterion total body volume, density and percent fat were determined by hydrostatic weighing. Validation of the regression equation resulted in validity coefficients of r = .99. The error in calculating percent fat was below ± 6% for all samples of subjects. It was concluded that the multiple regression equations reported for predicting total body volume and percent body fat are not population specific

A Non Population-Specific Method for Predicting Total Body Volume and Percent Fat

The validation of the segment zone approach as a non population-specific method for predicting total body volume and percent fat was investigated.The regression equation generated on 24 college-aged women, in a previous study, was validated on 47 prepubescent children, 22 college-aged men, 242 college-aged women, 84 middle-aged men and 60 middle-aged women. Segment zone girth measures were determined for all subjects. Criterion total body volume, density and percent fat were determined by hydrostatic weighing. Validation of the regression equation resulted in validity coefficients of r = .99. The error in calculating percent fat was below ± 6% for all samples of subjects. It was concluded that the multiple regression equations reported for predicting total body volume and percent body fat are not population specific