Andreas Kreutzer

• Doctor of Philosophy
• Research Scientist at Cook Children's Health Care System

Greater gains in power have been reported when incorporating cluster sets (CS) during hypertrophic training when compared to traditional set configurations (TS). The contributions of force and velocity as well as the metabolic response and the ability to sustain the initial load at hypertrophic intensities are unknown. PURPOSE: The purpose of this...

To compare kinetic, kinematic and hormonal responses during the parallel back squat, twelve resistance trained (RT; 6.1±2.1 years training), and twelve untrained (UT) men performed traditional (TRD; 4 sets x 10 repetitions; 120 s rest) and cluster sets (CLU; 4x(2x5); 30 s between clusters; 90 s between sets) at 70% 1RM. Significance was accepted at...

Non-invasive temperature monitoring with a sensor inside protective headgear may be effective in detecting temperatures that are associated with heat illness. To establish the relationship between in-hardhat temperatures (Tih) and core temperature (Tc) as measured by rectal (Tre) and esophageal (Tes) probes. Thirty males (age 24.57±4.32 yrs.) compl...

Background The ketogenic diet (KD) is the most popular carbohydrate restriction strategy for endurance athletes. However, because the primary goal of employing the KD is to gain a competitive advantage in competition, endurance athletes may be less concerned with the influence of the KD on their cardiometabolic health; particularly their blood lipi...

The aim of this study was to determine which characteristics of recreational, collegiate, and professional endurance athletes were associated with training changes due to COVID-19 safety restrictions. A Qualtrics survey was distributed to endurance athletes around the world from June 2020 to February 2021. Significant differences between athlete ch...

Proper nutrition is critical for optimal performance in endurance athletes. However, it is unclear if endurance athletes are meeting all their energy and nutrient needs. We examined if endurance athletes are meeting their nutritional requirements and if this differed by sex. Ninety-five endurance athletes (n = 95; 50.5% men; 34.9 ± 12.9 y) particip...

Extreme carbohydrate deficits during a ketogenic diet (KD) may result in metabolic adaptations reflective of low energy availability; however, the manifestation of these adaptations outside of exercise have yet to be elucidated in cyclists and triathletes. The purpose of this study is to investigate the chronic and postprandial metabolic responses...

Background Frequent dieting is common in athletes attempting to achieve a body composition perceived to improve performance. Excessive dieting may indicate disordered eating (DE) behaviors and can result in clinical eating disorders. However, the current nutrition patterns that underly dieting culture are underexplored in endurance athletes. Theref...

Endurance athletes frequently employ nutritional strategies to enhance performance. While professional organizations recommend high carbohydrate (HC) diets to maximize performance, many athletes, and researchers have recently shown renewed interest in the ketogenic diet (KD) in hopes to promote “fat adaptation”, which would allow athletes to make u...

Many endurance athletes have poor sleep quality which may affect performance and health. It is unclear how dietary intake affects sleep quality among athletes. We examined if sleep quality in endurance athletes is associated with consumption of fruit, vegetables, whole grains, dairy milk, and caffeinated beverages. Two hundred thirty-four endurance...

In order to achieve optimal performance, endurance athletes need to implement a variety of recovery strategies that are specific to their training and competition. Recovery is a multidimensional process involving physiological, psychological, emotional, social, and behavioral aspects. The purpose of the study was to examine current implementation,...

Purpose: The purpose of this study was to determine whether session rating of perceived exertion-derived training load (sRPE-TL) correlates with GPS-derived measures of external load in National Collegiate Athletics Association (NCAA) Division I female soccer athletes. Methods: Twenty-one NCAA Division 1 collegiate women’s soccer athletes (11 start...

High-sugar consumption is related to dyslipidemia. How acute exercise affects postprandial lipid and lipoprotein particle responses to a high-sugar meal (HSM) in postmenopausal women is unclear. We examined the effects of a late afternoon/early evening bout of aerobic exercise on postprandial lipid and lipoprotein particle responses to a HSM breakf...

Endurance athletes may implement rigid dietary strategies, such as the ketogenic diet (KD), to improve performance. The effect of the KD on appetite remains unclear in endurance athletes. This study analyzed the effects of a KD, a high-carbohydrate diet (HCD), and habitual diet (HD) on objective and subjective measures of appetite in trained cyclis...

The primary means of disseminating sport and exercise science research is currently through journal articles. However, not all studies, especially those with null findings, make it to formal publication. This publication bias towards positive findings may contribute to questionable research practices. Preregistration is a solution to prevent the pu...

BACKGROUND Obesity is a complex inflammatory disease characterized by an accumulation of abdominal visceral fat that increases cardiovascular risk factors. Chronic exposure to inflammation leads to endothelial dysfunction where response to sheer stress is inadequate to promote smooth muscle relaxation and thus healthy arterial dilation. When combin...

Inactivity‐related diseases such as cardiovascular disease (CVD) involve a complex interplay among endothelial cells, leukocytes and activated platelets in response to vascular injury. Activated platelets are involved in atherogenesis and can promote an inflammatory phenotype of both the vasculature and leukocytes, particularly monocytes. Platelet‐...

Here, we propose a novel theoretical model linking present-focused decision-making to the activities of the immune system. We tested our model by examining the relationship between inflammatory activity – in vivo and in vitro – and decision-making characterized by impulsivity, present focus, and an inability to delay gratification. Results support...

High-sugar intake may cause endothelial dysfunction. It is unknown if a bout of aerobic exercise improves endothelial dysfunction caused by a high-sugar meal in postmenopausal women. This study evaluated if prior aerobic exercise attenuates postprandial endothelial dysfunction in postmenopausal women. Twenty-two postmenopausal women (age [mean±SD]:...

The primary means for disseminating sport and exercise science research is currently through journal articles. However, not all studies, especially those with null findings, make it to formal publication. This publication bias towards positive findings may contribute to questionable research practices. Preregistration is a solution to prevent the pub...

Kreutzer, A, Martinez, CA, Kreutzer, M, Stone, JD, Mitchell, JB, and Oliver, JM. Effect of ACTN3 polymorphism on self-reported running times. J Strength Cond Res XX(X): 000-000, 2018-This investigation examined the effect of ACTN3 genotype on self-reported distance running personal records (PRs). Of 94 (n = 94) recreationally active men and women,...

Our aim was to determine the effects of probiotic supplementation (Bifidobacterium longum 35624; 1 billion CFU·d⁻¹) on exercise performance, immune modulation, and cognitive outlook in collegiate female athletes during six weeks of offseason training. Seventeen National Collegiate Athletic Association (NCAA) Division 1 collegiate female swimmers pa...

Alpha-actinins form a crosslink between actin filaments and adjacent sarcomeres, and play a role in signaling and energy metabolism. Alpha-actinin-3, encoded by the ACTN3 gene, only presents in Type II muscle fibers. Homozygosity for the 577X allele (XX) results in complete deficiency of α-actinin-3, whereas heterozygosity (RX) and homozygosity for...

The purpose of this study was to examine changes in creatine kinase and hormones over the course of an entire season of American football. A secondary purpose was to determine differences between starters and non-starters. Fasting blood samples were obtained from nineteen National Collegiate Athletic Association Division I (n = 19; 20 ± 1 years) fo...

The purpose of this study was to compare the kinematic, metabolic, endocrine, and perceptual responses of three back squat protocols with equal loads, number of repetitions, and total rest duration. Eight strength-trained men performed 36 back squats using 75% 1RM and 420 s of total rest during basic cluster sets of 4 (CS4), rest-redistribution set...

This study compared the acute cytokine response, and kinetic and kinematic profile following back squat exercise in resistance-trained men. In a randomized, cross-over design, 10 resistance-trained men (27±4 y, 1.80±0.07 m, 82.8±6.7 kg, 16.3±3.5% fat) performed the back squat exercise using traditional and cluster set configurations. Kinetic and ki...

Effects of MusclePharm Assault BlackTM on lower extremity spinal excitability and postactivation potentiation: A pilot study Brian Wallace*, Haley Bergstrom, Kelly Wallace Department of Kinesiology and Health Promotion, University of Kentucky, Lexington, KY 40506, USA Email: brian.wallace@uky.edu; brian.wallace@northern.edu Background: Caffeine h...

Cortisol, a glucocorticoid released from the adrenal gland, is a purported biomarker for whole body stress. Contact sports, such as football, consist of periods of intense training and repetitive high impact collisions; both of which may result in possible skeletal muscle damage and increase cortisol levels. Therefore, this investigation sought to...

Myokines, expressed and released by muscle fibers, play an important role in the metabolic and immunological response to resistance exercise. This study examined the effects of cluster sets (CS) and traditional sets (TS) on the myokines IL-6 and IL-15 during the parallel back squat exercise (BS) in resistance-trained men. A main effect for TIME was...

The addition of bovine colostrum to a resistance program designed to elicit hypertrophy appears to augment FFM gains to a greater degree when compared with a commercially available bio-active peptide supplement. Furthermore, bovine colostrum seems to allow decreases in fat mass and percent body fat concurrent with increases in FFM. However, further...

Presented at Annual ACSM Meeting

Introduction The purpose of this case series was to investigate the respiratory effects of weight loss or gain in obese children over 1 yr. Methods Two obese children filled out the physical activity questionnaire for children (PAQ‐C) and underwent pulmonary function testing, dual‐energy x‐ray absorptiometry, maximal exercise testing, and constant...

Curcumin, a turmeric extract, may protect against cardiovascular diseases by enhancing endothelial function. In this randomized controlled double-blind parallel prospective study, fifty-nine healthy adults were assigned to placebo, 50 mg (50 mg), or 200 mg (200 mg) curcumin, for 8 weeks. The higher curcumin (200 mg) supplementation produced a dose-...

In traditional sets (TRD) repetitions are performed continuously, whereas cluster sets (CLU) allow a brief rest between groups of repetitions. We investigated the acute mechanical, metabolic, and hormonal response to CLU in men. Twelve resistance-trained (RT) and 11 untrained (UT) men performed TRD (4 × 10 repetitions with 2 min rest) and CLU [4 ×...

This investigation compared the kinetics and kinematics of cluster sets (CLU) and traditional sets (TRD) during back squat in trained (RT) and untrained (UT) men. Twenty-four participants (RT=12, 25±1 years, 179.1±2.2 cm, 84.6±2.1 kg; UT=12, 25±1 years, 180.1±1.8 cm, 85.4±3.8 kg) performed TRD (4 x 10 120 s rest) and CLU (4 x (2 x 5) 30 s between c...

Oliver, JM, Kreutzer, A, Jenke, SC, Phillips, MD, Mitchell, JB, and Jones, MT. Velocity drives greater power observed during back squat using cluster sets. J Strength Cond Res 30(1): 235– 243, 2016—This investigation compared the kinetics and kine-matics of cluster sets (CLU) and traditional sets (TRD) during back squat in trained (RT) and untraine...