Citrus Aurantium and caffeine complex versus placebo on biomarkers of metabolism: a double blind crossover design

BACKGROUOND: The purpose of this study was to examine resting the metabolic response to the ingestion of a complex containing Citrus Aurantium + Caffeine (CA + C) and if its consumption influences metabolic recovery following a high-intensity anaerobic exercise bout in habitual caffeine users. METHODS: Ten physically active males (25.1 ± 3.9 years; weight 78.71 ± 9.53 kg; height 177.2 ± 4.6 cm; body fat 15.5 ± 3.13%) participated in this study. This study was performed in a double-blind, randomized crossover fashion consisting of two exhaustive exercise protocols. On each visit the participants consumed either a CA + C (100 mg of CA and 100 mg of C) or placebo (dextrose) capsule. After consumption, participants were monitored throughout a 45-min ingestion period, then completed a repeated Wingate protocol, and were then monitored throughout a 45-min recovery period. Metabolic function was measured through blood glucose, plasma insulin, plasma triglycerides, and plasma catecholamines: epinephrine (E) and norepinephrine (NE). Biomarkers were taken at four different time points; Ingestion period: baseline (I1), post-ingestion period (I2); Recovery period: immediately post-exercise (R1), post-recovery period (R2). RESULTS: A repeated measures ANOVA revealed significant time-dependent increases in plasma E and NE at I2 only in the CA + C trial (p \u3c 0.05), and a significant decrease in blood glucose at I2 in the PLA trial (p \u3c 0.05); however, no meaningful changes in glucose was observed following CA + C ingestion. No changes in insulin or triglycerides were observed during the ingestion period. No trial-dependent differences were observed in the Recovery period. All biomarkers of metabolic recovery were equivalent when evaluating R1 v R2. Participants recovered in a similar time-dependent manner in all markers of metabolism following the PLA and CA + C trials. CONCLUSION: The findings of this study suggested that normal recommended dosages of 100 mg CA + 100 mg C is sufficient to promote glucose sparing at rest, with modest increases in SNS activity; however, the individual role of CA or C in this response cannot be determined

The Influence of Citrus urantium and Caffeine Complex versus Placebo on the Cardiac Autonomic Response: A Double Blind Crossover Design

Background: The purpose of this study was to examine the resting cardiac autonomic nervous system’s response to the ingestion of a complex containing Citrus aurantium + Caffeine (CA + C) and its influence on recovery following a high-intensity anaerobic exercise bout in habitual caffeine users. Methods: Ten physically active males (25.1 ± 3.9 years; weight 78.71 ± 9.53 kg; height 177.2 ± 4.6 cm; body fat 15.5 ± 3.13%) participated in this study, which consisted of two exhaustive exercise protocols in a randomized crossover design. On each visit the participants consumed either a CA + C (100 mg of CA and 100 mg of C) or placebo (dextrose) capsule. After consumption, participants were monitored throughout a 45-min ingestion period, then completed a repeated Wingate protocol, and were then monitored throughout a 45-min recovery period. Cardiac autonomic function (Heart Rate (HR) and Heart Rate Variability (HRV)) and plasma epinephrine (E) and norepinephrine(NE) were taken at four different time points; Ingestion period: baseline (I1), post-ingestion period (I2); Recovery period: immediately post-exercise (R1), post-recovery period (R2). Heart rate variability was assessed in 5-min increments. Results: A repeated measures ANOVA revealed significant time-dependent increases in HR, sympathetic relatedmarkers of HRV, and plasma E and NE at I2 only in the CA + C trial (p\u3c 0.05); however, no meaningful changes in parasympathetic markers of HRV were observed. Participants recovered in a similar time-dependent manner in all markers of HRV and catecholamines following the PLA and CA + C trials. Conclusion: The consumption of CA + C results in an increase of sympathetic activity during resting conditions without influencing parasympathetic activity. CA + C provides no influence over cardiac autonomic recovery

Metabolic biomarkers following a short and long bout of high-intensity functional training in recreationally trained men

Glucose regulation is a fundamental process of metabolic function, and is acutely altered by physical activity. High-Intensity Functional Training (HIFT) is a form of exercise performed using combinations of various modalities and durations. It is unknown if the metabolic responses to HIFT are similar to more commonly studied modalities (e.g., cycling and treadmill exercise), or if exercise duration will influence glucose regulation. The purpose of this study was to determine the effect of a Short (0.05), except for lowered 3HR E (p=0.007). This study demonstrated that both SHORT and LONG bouts of HIFT elicited GLU, INS, E, and NE responses similar to those reported in response to high-intensity treadmill and cycling exercise, and that duration of the HIFT bouts may not be a determining factor in glucose regulation in healthy individuals

A Comparison of Anaerobic Power Tests using Cycle Ergometry and Non-motorized Treadmill Ergometry at Optimized Loads

International Journal of Exercise Science 16(4): 1293-1305, 2023. The purpose of this study was to compare performance markers derived from a 30-second maximal bout on a cycle ergometer (CE) and non-motorized treadmill (NMT) under optimized loads. Recreationally active participants (n = 40) volunteered for the study. Force-velocity tests on the CE and NMT were used to determine optimal resistance for peak power (PP) production. The remaining visits were randomized and counterbalanced, with a single 30-second maximal test on CE or NMT to assess PP, mean power (MP), fatigue index (FI), over the course of the 30-second test, and maximum heart rate (HRmax) and blood lactate (BLa-) taken 1-minute post. Results were that PP and MP were higher (P\u3c0.05) on CE compared to NMT for both sexes. FI did not differ among males (P=0.201) whereas females showed higher FI (P=0.002) on the CE. HRmax and BLa- were higher (P\u3c0.05) after NMT for both sexes. There was no difference for optimal braking force on NMT between males (16.65±4.49%BW) and females (14.30±3.10%BW) (P=0.061). CE optimal torque factor was higher for males (0.78±0.16 Nm/kg) compared to females (0.62±0.14 Nm/kg) (P=0.001). Overall, CE produced higher power output using optimized loads in recreationally active males and females, while NMT test resulted in a higher HRmax andBLa- concentration. These tests for anaerobic power, when performed with optimized loads, produced different results for several variables, therefore these modalities should not be considered interchangeable. Practitioners should consider which modality best mimics the activities of the person being tested when selecting a protocol

Carbohydrate Rinse Fails to Enhance Cycling Performance or Alter Metabolic and Autonomic Recovery in Recreational Cyclists

The purpose of the study was to examine the effects of carbohydrate (CHO) mouth rinsing on autonomic and metabolic recovery as well as cycling performance. Ten male recreational cyclists (age = 30 ± 6 years, VO2peak = 54.5 ± 8.1 mL·kg-1·min-1) completed a randomized, double-blind, placebo-controlled, crossover designed study. A CHO or a placebo (PLA) rinse was administered every 12.5% of a work to completion trial (75%Wmax). Heart rate variability (lnRMSSD), the respiratory exchange ratio, and plasma epinephrine, norepinephrine, insulin, glucose, free fatty acids (FFA), and lactate were measured pre- and post-exercise. The CHO rinse did not improve time to completion of the test trial (CHO: 4108 ± 307 s, PLA: 4176 ± 374 s, p = 0.545). Further, the CHO rinse did not impact autonomic recovery, as measured by lnRMSSD (p = 0.787) and epinephrine (p = 0.132). Metabolic biomarkers were also unaffected by the CHO rinse, with no differences observed in responses of FFA (p = 0.064), lactate (p = 0.302), glucose (p = 0.113) or insulin (p = 0.408). Therefore, the CHO mouth rinse does not reduce the acute sympathetic response following strenuous exercise and does not result in improvements in cycling time to completion

Acute inflammatory responses to high-intensity functional training programming: An observational study

Effects of varying types of short duration workouts in high-intensity functional training (HIFT) on inflammatory biomarkers have not been adequately characterized. Objectives: The purpose of this descriptive study was to examine the acute effects of HIFT workouts on biomarkers of inflammation, over time, in two HIFT bouts. Materials and Methods: Ten apparently healthy males (28.1 ± 5 yrs) completed two HIFT sessions (“short bout:” sub-5-minute vs. “long bout:” 15-minute) in a randomized crossover design. Blood was drawn pre and post-exercise, and 1 hour, 3 hours, and 6 hours post-exercise, centrifuged, and plasma frozen for analysis. Inflammation was assessed through plasma interleukin-6 (IL-6), interleukin-10 (IL-10), and tumour necrosis factor alpha (TNF-α). Results: Repeated measures ANOVA revealed a single trial-dependent difference (IL-6, p≤ 0.05), and while statistically significant, this difference may not be biologically significant. The biomarkers IL-6, IL-10, and TNF-α all follow a similar pattern of peaking post-exercise and returning to baseline within 6 hours in both trials. Conclusions: Both temporal responses and concentrations were similar in the short and long bout. A practical implication is that both bouts of a HIFT elicit certain specific physiologic inflammatory responses

Utility of an Isotonic Beverage on Hydration Status and Cardiovascular Alterations

This study determined the beverage hydration index (BHI) and postprandial cardiac autonomic activity after consuming an isotonic beverage (IB) compared to distilled water (DW). Twenty-two participants (50% female; mean ± SD; age, 27 ± 3 year; height, 169.1 ± 12.6 cm; weight, 73.3 ± 13.8 kg; BF%, 23 ± 10%) completed two experimental trials where they consumed 1 L DW or an IB; after which urine volume and cardiac autonomic activity was measured through 240 min. Cardiac autonomic activity was quantified using heart rate (HR), log transformed heart rate variability measures (root mean square of successive R–R intervals; RMSSD; low frequency, LF; and high frequency, HF) and systolic time intervals (pre-ejection period, PEP). BHI was significantly greater after IB consumption at min 0 (MD [95% CI]; 1.31 [0.35, 2.27]), 180 min (0.09 [0.022, 0.16]), and 240 min (0.1 [0.03, 0.17]) compared to DW (p = 0.031). Net fluid balance was significantly greater in IB than DW at 180 min (90 [−16.80, 196.81]) and 240 min (106 [−13.88, 225.88]) (p = 0.037). HR decreased over time in both beverage trials but was higher following IB ingestion at 0 min (3.9 [−2.42, 10.22]), 30 min (5.3 [−0.94, 11.54]), and 60 min (2.7 [−3.42, 8.82]) (p = 0.0002). lnHF was greater 30 min post DW ingestion compared to IB (0.45 [−0.23, 1.13]) (p = 0.039). IB promotes greater fluid retention capacity compared to DW within 4 hours of consumption. The variations in cardiac autonomic measures may warrant further investigation in clinical populations (i.e., patients with autonomic failure)

Resting Vagal Tone Following a 16-Week High-Intensity Functional Training Intervention: 2110 Board #262 June 2, 3: 30 PM - 5: 00 PM

PURPOSE: The purpose of this study was to examine alterations in resting vagal tone through the measurement of heart rate variability (HRV) over a 16-week CF training program. METHODS: Nine apparently healthy females (35.8 ± 9.25 years) participated in this study. On two separate occasions, Pre and Post 16-week, participants attended the Exercise Science lab in order to obtain a 10-minute resting HRV recording using Polar Team2 monitors (Lake Success, NY). In order to quantify HRV, the last five-minute segments of each 10-minute recording were analyzed using online Kubios software (Version 2.2). The markers used to quantify HRV were the time domain of the Root Mean Square of Successive Differences (RMSSD) and the High-frequency (HF) of the power spectrum density. RESULTS:Data was log transformed due to a violation of normality and expressed as lnRMSSD and lnHF. Paired sample t-tests showed no significant differences between pre and post lnRMSSD (Pre: 1.60 ± 0.24 ms2, Post: 1.64 ± 0.20 ms2; p = 0.510) and lnHF (Pre: 1.68 ± 0.18 ms2, Post: 1.70 ± 0.19 ms2; p = 0.765). CONCLUSIONS:16-weeks of HIFT was not sufficient enough to significantly influence markers of resting vagal tone

Acute Effect of Popular High-Intensity Functional Training Exercise on Physiologic Markers of Growth

Constantly evolving, high-intensity functional training (HIFT) exercise consists of various modalities, orders, weights, and repetition schemes. High-intensity functional training has gained popularity among the general population, but lacks empirical evidence regarding acute adaptive responses. The purpose of this study was to describe the acute effects of 2 representative bouts of HIFT on physiologic markers of growth. For convenience, the bouts are designated “short” (\u3c5 \u3eminutes) and “long” (∼15 minutes), although duration was not the only difference between bouts. Ten apparently healthy men (28.1 ± 5 years) performed 2 HIFT bouts in a randomized crossover design. Blood was collected at 5 time points (Pre, Post, 1, 3, and 6 hours) to examine growth hormone (GH), insulin-like growth factor (IGF-1), insulin-like growth factor binding proteins 1 and 2 (IGFBP-1 and IGFBP-2), and vascular endothelial growth factor (VEGF). Blood lactate concentration ([La]) was analyzed at the Pre and Post time points. A repeated-measures analysis of variance (ANOVA) revealed no trial differences among the markers (IGF-1, IGFBP-1, IGFBP-2, and VEGF) except GH at Post, where the long bout produced a greater effect (p = 0.005). Mean GH levels (pg·ml−1) in the short bout increased from 68.4 to 106.5, and in the long bout, mean GH levels increased from 38.5 to 286.4. The repeated-measures ANOVA revealed a main time effect in GH (p = 0.037), while a post hoc t-test demonstrated elevated GH at 1 hour (p = 0.018) when compared with Pre. No time-dependent change (p \u3e 0.05) was observed in IGF-1, IGFBP-1, IGFBP-2, or VEGF. Mean blood [lactate] increased more than tenfold in both bouts. The findings of this descriptive study suggest that, other than GH, there are no acute differences in markers of skeletal muscle or vascular growth between these 2 specific HIFT bouts

Autonomic response to a short and long bout of high-intensity functional training

The evaluation of Autonomic Nervous System (ANS) recovery following exercise provides insight into the transient stress placed on the cardiovascular system. High-Intensity Functional Training (HIFT) is a form of intense exercise that is prescribed in various modalities and durations; however, little is known about the influence of HIFT duration on ANS recovery. Ten apparently healthy males (28.1 ± 5.4 yrs) performed two HIFT sessions (\u3c5-minute and 15-minute) in a crossover fashion. ANS activity was measured using plasma Epinephrine (E) and Norepineprine (NE); Heart Rate Variability markers of the log transformed Root Mean Square of Successive Differences (lnRMSSD) and High-Frequency power (lnHF). No trial dependent differences were observed in lnRMSSD (p = 0.822), lnHF (p = 0.886), E (p = 0.078), or NE (p = 0.194). A significant main time effect was observed in both trials with a depression in lnRMSSD and lnHF following the trials (p \u3c 0.05) and recovering by 2-hours post (p = 0.141, p \u3e 0.999) respectively. A trial dependent increase in E and NE occurred immediately post (p \u3c 0.05) and recovered by 1-hour post (p \u3e 0.999, p \u3e 0.999) respectively. The HIFT bouts examined within this study demonstrated similar transient strain of the ANS