Stacy J. Ingraham

Psoriasis and physical activity: a review.

Psoriasis is a common, chronic inflammatory skin disease that can cause significant discomfort and impairment to quality of life. Recent research indicates that individuals with moderate‐to‐severe psoriasis are likely at greater risk for chronic cardiometabolic co‐morbidities such as cardiovascular disease, type 2 diabetes, obesity and metabolic syndrome. Physical activity can be an effective primary and adjunctive treatment for these maladies in other populations. Unfortunately, only a limited number of studies have examined physical activity in psoriasis, which are limited by poor design and lack of validated physical activity assessment methodologies. A variety of data suggest shared physiologic pathways between physical activity, psoriasis, and psoriasis cardiometabolic co‐morbidities. Increased adiposity, inflammation, oxidative stress, adhesion molecules and lipids are physiologically linked to psoriasis, the risk of psoriasis cardiometabolic co‐morbidities, and low levels of physical activity. In addition, epigenetic pathways are involved in psoriasis and could be influenced by physical activity. The physical and psychosocial impairments common in psoriasis may make it difficult to participate in regular physical activity, and future studies should aim to determine if physical activity interventions improve functioning and reduce co‐morbidities in psoriasis.

Psoriasis and physical activity

Psoriasis is a common, chronic inflammatory skin disease that can cause significant discomfort and impairment to quality of life. Recent research indicates that individuals with moderate‐to‐severe psoriasis are likely at greater risk for chronic cardiometabolic co‐morbidities such as cardiovascular disease, type 2 diabetes, obesity and metabolic syndrome. Physical activity can be an effective primary and adjunctive treatment for these maladies in other populations. Unfortunately, only a limited number of studies have examined physical activity in psoriasis, which are limited by poor design and lack of validated physical activity assessment methodologies. A variety of data suggest shared physiologic pathways between physical activity, psoriasis, and psoriasis cardiometabolic co‐morbidities. Increased adiposity, inflammation, oxidative stress, adhesion molecules and lipids are physiologically linked to psoriasis, the risk of psoriasis cardiometabolic co‐morbidities, and low levels of physical activity. In addition, epigenetic pathways are involved in psoriasis and could be influenced by physical activity. The physical and psychosocial impairments common in psoriasis may make it difficult to participate in regular physical activity, and future studies should aim to determine if physical activity interventions improve functioning and reduce co‐morbidities in psoriasis.

Association Between Vitamin D Status and Maximal-Intensity Exercise Performance in Junior and Collegiate Hockey Players.

Abstract Fitzgerald, JS, Peterson, BJ, Warpeha, JM, Johnson, SC, and Ingraham, SJ. Association between vitamin D status and maximal-intensity exercise performance in junior and collegiate hockey players. J Strength Cond Res 29(9): 2513–2521, 2015—Recent evidence suggests that athletes are at risk for poor vitamin D status. This study used a cross-sectional design to investigate the strength of association between 25-hydroxyvitamin D (25(OH)D) concentration and measures of maximal-intensity exercise performance in competitive hockey players. Fifty-three collegiate and junior male ice hockey players training near Minneapolis, MN (44.9° N latitude) participated in the study during the off-season (May 16–June 28). Circulating 25(OH)D concentration, grip strength, vertical jump performance, and power production during the Wingate Anaerobic Test (WAnT) were evaluated. Despite no athletes with 25(OH)D concentration indicative of deficiency (<20 ng·mL−1), positive bivariate correlations were detected between vitamin D status, relative grip strength (p = 0.024), and peak power during the WAnT (p = 0.035). Only for relative grip strength (p = 0.043), did 25(OH)D concentration predict performance after adjusting for level of play, fat-free mass, fat mass, and self-reported total physical activity in sequential linear regression. Vitamin D status was positively associated with starting gradient (p = 0.020) during the squat jump, with higher concentrations associated with increased rate of force development in the initial portion of the jump. Interventional trials should investigate the impact of vitamin D supplementation on maximal-intensity exercise performance outcomes and rate of force development in large samples of vitamin D–deficient athletes while controlling for training exposure. Our data indicate that if vitamin D status is causally related to maximal-intensity exercise performance in athletes, the effect size is likely small.

Glucose‐fructose likely improves gastrointestinal comfort and endurance running performance relative to glucose‐only

This study aimed to determine whether glucose‐fructose (GF) ingestion, relative to glucose‐only, would alter performance, metabolism, gastrointestinal (GI) symptoms, and psychological affect during prolonged running. On two occasions, 20 runners (14 men) completed a 120‐min submaximal run followed by a 4‐mile time trial (TT). Participants consumed glucose‐only (G) or GF (1.2:1 ratio) beverages, which supplied ∼ 1.3 g/min of carbohydrate. Substrate use, blood lactate, psychological affect [Feeling Scale (FS)], and GI distress were measured. Differences between conditions were assessed using magnitude‐based inferential statistics. Participants completed the TT 1.9% (−1.9; −4.2, 0.4) faster with GF, representing a likely benefit. FS ratings were possibly higher and GI symptoms were possibly‐to‐likely lower with GF during the submaximal period and TT. Effect sizes for GI distress and FS ratings were relatively small (Cohens d = ∼0.2 to 0.4). GF resulted in possibly higher fat oxidation during the submaximal period. No clear differences in lactate were observed. In conclusion, GF ingestion – compared with glucose‐only – likely improves TT performance after 2 h of submaximal running, and GI distress and psychological affect are likely mechanisms. These results apply to runners consuming fluid at 500–600 mL/h and carbohydrate at 1.0–1.3 g/min during running at 60–70% VO2peak.

Division I Hockey Players Generate More Power Than Division III Players During on- and Off-Ice Performance Tests.

Abstract Peterson, BJ, Fitzgerald, JS, Dietz, CC, Ziegler, KS, Ingraham, SJ, Baker, SE, and Snyder, EM. Division I hockey players generate more power than Division III players during on- and off-ice performance tests. J Strength Cond Res 29(5): 1191–1196, 2015—Current research has found anthropometric and physiological characteristics of hockey players that are correlated to performance. These characteristics, however, have never been examined to see whether significant differences exist between on- and off-ice performance markers at different levels of play; Division I, Elite Junior, and Division III. The purpose of this study was to examine the differences that may exist between these characteristics in Division I (24), Elite Junior (10), and Division III hockey (11) players. Forty-five (age: 18–24 years) hockey players completed anthropometric, on-ice, and off-ice tests to ascertain average measures for each division of play. On-ice testing was conducted in full hockey gear and consisted of acceleration, top-speed, and on-ice repeated shift test (RST). Off-ice tests included vertical jump, Wingate, grip strength, and a graded exercise test performed on a skating treadmill to ascertain their . Division I players had significantly lower body fat than their Division III peers (p = 0.004). Division I players also scored significantly better on measures of anaerobic power; vertical jump (p = 0.001), Wingate peak power (p = 0.05), grip strength (p = 0.008), top speed (p = 0.001), and fastest RST course time (p = 0.001) than their Division III counterparts. There was no significant difference between Division I and Elite Junior players for any on- or off-ice performance variable. The results of this study indicate that performance differences between Division I and Division III hockey players seem to be primarily because of the rate of force production.

Aerobic capacity is associated with improved repeated shift performance in hockey.

Abstract Peterson, BJ, Fitzgerald, JS, Dietz, CC, Ziegler, KS, Ingraham, SJ, Baker, SE, and Snyder, EM. Aerobic capacity is associated with improved repeated shift performance in hockey. J Strength Cond Res 29(6): 1465–1472, 2015—Current research has found conflicting results regarding the relationship between maximal oxygen uptake (V[Combining Dot Above]O2peak) and the repeated sprint ability (RSA) of hockey players. The purpose of this study was to use sport-specific testing methods to investigate this relationship. Forty-five (range, 18–24) college hockey players completed a graded exercise test on a skating treadmill to ascertain their V[Combining Dot Above]O2peak. An on-ice repeated shift test was then conducted to evaluate each players susceptibility to fatigue. First gate, second gate, and total test times were collected on the course and then used to calculate associated decrement scores. Second gate decrement was significantly correlated to V[Combining Dot Above]O2peak (r = −0.31, p = 0.04). Final stage completed during the graded exercise test was also significantly correlated to second gate and total decrement (r = −0.46, p = 0.001; r = −0.32, p = 0.03). No significant correlation was found between either first gate or total decrement score and V[Combining Dot Above]O2peak (r = −0.11, p = 0.46; r = −0.17, p = 0.26). The results of this study indicate that RSA is associated with V[Combining Dot Above]O2peak and final stage completed when using sport-specific testing methods.

Vitamin D status is associated with adiposity in male ice hockey players.

UNLABELLED The prevalence of insufficient vitamin D status is of concern and may negatively affect health and physical performance. PURPOSE The purpose of this study was twofold, as follows: to assess the prevalence of 25-hydroxyvitamin D (25(OH)D) insufficiency among young hockey players and evaluate the association between 25(OH)D concentration and fat mass (FM) after adjusting for covariates. METHODS Data were collected for 53 junior and collegiate ice hockey players residing near Minneapolis, MN (44.9° N) during the off-season (May 16 to June 28). Liquid chromatography-tandem mass spectrometry was used to assess 25(OH)D concentration, and hydrostatic weighing was used to determine FM. Dietary intake and endogenous synthesis of vitamin D were evaluated via a questionnaire. RESULTS Twenty (37.7%) athletes possessed insufficient 25(OH)D concentrations (<32 ng·mL(-1)). Log-transformed 25(OH)D concentration was inversely associated with FM in the athletes (r = -0.52, n = 51, P = 0.001). After controlling for measured covariates using sequential linear regression, the adjusted R2 change value indicated that 8.1% of the variability in (log of) 25(OH)D concentration was predicted by FM (P = 0.005). CONCLUSIONS The findings of this study demonstrate an inverse association between FM and vitamin D status after adjusting for environmental, dietary, and anthropometric predictors in a sample population of athletes. Athletes with higher levels of adiposity may be at increased risk of poor vitamin D status.

Saccharide Composition of Carbohydrates Consumed during an Ultra-endurance Triathlon.

Objective: Ingesting a mix of glucose and fructose during exercise increases exogenous carbohydrate oxidation while minimizing gastrointestinal (GI) distress. Several studies have suggested that a glucose-to-fructose ratio of 1.2:1 to 1:1 is optimal. No studies have quantified saccharides consumed during a nonsimulated endurance event. The aim of this investigation was to quantify saccharide sources used during an ultra-endurance triathlon and provide a resource for athletes desiring to manipulate the saccharide content of carbohydrate consumed during training and competition. Methods: Participant self-report and direct measurement were used to assess foods and beverages consumed during an ultra-endurance (70.3-mile) triathlon. Manufacturer-supplied information, high-performance liquid chromatography, and the US Department of Agriculture Food Database were used to quantify saccharide profiles of foods and beverages. Participants reported GI distress during the run on a 0–10 scale. A subanalysis examined associations between saccharides and GI distress among participants consuming ≥ 50 g·h−1 of carbohydrate during the swim and cycle. Results: Fifty-four participants (43 men) used 80 foods and beverages with a unique saccharide profile. Of total carbohydrate, median proportions as glucose, fructose, and sucrose were 64%, 5%, and 10%, and only 7 foods (8.8%) had a glucose-to-fructose ratio of 1.2:1 to 1:1. The median glucose-to-fructose ratio of carbohydrate ingested was 2.9:1 (2.2:1–5.3:1). Twenty participants consumed ≥ 50 g·h−1 of carbohydrate during the swim and cycle, and significant correlations with incident GI distress at mile 1 of the run were found for glucose (r = 0.480, p = 0.032) and fructose (r = −0.454, p = 0.044). Conclusions: The majority of foods and beverages consumed during an ultra-endurance triathlon did not contain an optimal saccharide profile. Furthermore, glucose intake was associated with greater GI distress among participants consuming a high rate of carbohydrate.

Vitamin D status and V[combining dot above]O2peak during a skate treadmill graded exercise test in competitive ice hockey players.

Abstract Fitzgerald, JS, Peterson, BJ, Warpeha, JM, Wilson, PB, Rhodes, GS, and Ingraham, SJ. Vitamin D status and V[Combining Dot Above]O2peak during a skate treadmill graded exercise test in competitive ice hockey players. J Strength Cond Res 28(11): 3205–3210, 2014—Vitamin D status has been associated with cardiorespiratory fitness (CRF) in cross-sectional investigations in the general population. Data characterizing the association between 25-hydroxyvitamin D (25(OH)D) concentration and CRF in athletes are lacking. Junior and collegiate ice hockey players were recruited from the Minneapolis, MN (44.9° N), area during the off-season period (May 16–June 28). The purpose of this study was to examine the cross-sectional association between 25(OH)D concentration and CRF in a sample population of competitive ice hockey players. Circulating 25(OH)D level was assessed from a capillary blood sample analyzed using liquid chromatography-tandem mass spectrometry. V[Combining Dot Above]O2peak during a skate treadmill graded exercise test (GXT) was used to assess CRF. Data on both 25(OH)D concentration and V[Combining Dot Above]O2peak were available for 52 athletes. Insufficient 25(OH)D concentrations were found in 37.7% of the athletes (<32 ng·ml−1). Vitamin D status was not significantly associated with any physiological or physical parameter during the skate treadmill GXT.

Self-Report Versus Direct Measurement for Assessment of Fluid Intake During a 70.3-Mile Triathlon

PURPOSE Self-report (SR) has been the primary method used to assess fluid intake during endurance events, but unfortunately, little is known about the validity of SR. The purpose of this study was to compare SR fluid intake with direct measurement (DM) during a 70.3-mile triathlon. METHODS Fifty-three (42 men, 11 women) individuals competing in a 70.3-mile triathlon participated in the study. On the 13.1-mile-run section of the triathlon, 11 research stations provided fluid in bottles filled with 163 mL of water or carbohydrate-electrolyte beverage (CEB). Participants submitted bottles 25 m past aid stations to be reweighed postrace. Participants also answered questions regarding fluid intake postrace. Bland-Altman plots and 95% limits of agreement were used to assess precision of the measures, while least-squares regression assessed linear agreement. RESULTS SR intakes during the run ranged from 0-1793, 0-1837, and 0-2628 mL for water, CEB, and total fluid, with corresponding DM intakes of 0-1599, 0-1642, and 0-2250 mL. DM and SR showed strong linear agreement for water, CEB, and total fluid (R2=.71, .80, and .80). Mean differences between the measures on the Bland-Altman plots were small (13-41 mL), but relatively large differences (±500 mL) between the measures were apparent for some participants. CONCLUSIONS SR is the predominant methodology used in field studies assessing hydration, despite little to no data confirming its validity. The results herein suggest that fluid-intake-assessment methodology should be chosen on a case-by-case basis and that caution should be used when interpreting data based on SR.