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Physiological, kinematic, and electromyographic responses to kinesiology-type patella tape in elite cyclists

Hébert-Losier K, Yin NS, Beaven CM, Tee CCL, Richards J

J Electromyogr Kinesiol, 2019 Feb;44:36-45.
PMID: 30496944 DOI: 10.1016/j.jelekin.2018.11.009

Kinesiology-type tape (KTT) has become popular in sports for injury prevention, rehabilitation, and performance enhancement. Many cyclists use patella KTT; however, its benefits remain unclear, especially in uninjured elite cyclists. We used an integrated approach to investigate acute physiological, kinematic, and electromyographic responses to patella KTT in twelve national-level male cyclists. Cyclists completed four, 4-minute submaximal efforts on an ergometer at 100 and 200 W with and without patella KTT. Economy, energy cost, oxygen cost, heart rate, efficiency, 3D kinematics, and lower-body electromyography signals were collected over the last minute of each effort. Comfort levels and perceived change in knee stability and performance with KTT were recorded. The effects of KTT were either unclear, non-significant, or clearly trivial on all collected physiological and kinematic measures. KTT significantly, clearly, and meaningfully enhanced vastus medialis peak, mean, and integrated electromyographic signals, and vastus medialis-to-lateralis activation. Electromyographic measures from biceps femoris and biceps-to-rectus femoris activation ratio decreased in either a significant or clinically meaningful manner. Despite most cyclists perceiving KTT as comfortable, increasing stability, and improving performance, the intervention exerted no considerable effects on all physiological and kinematic measures. KTT did alter neuromuscular recruitment, which has potential implications for injury prevention.
Fulltext Mechanisms for Combined Hypoxic Conditioning and Divergent Exercise Modes to Regulate Inflammation, Body Composition, Appetite, and Blood Glucose Homeostasis in Overweight and Obese Adults: A Narrative Review

Tee CCL, Cooke MB, Chong MC, Yeo WK, Camera DM

Sports Med, 2023 Feb;53(2):327-348.
PMID: 36441492 DOI: 10.1007/s40279-022-01782-0

Obesity is a major global health issue and a primary risk factor for metabolic-related disorders. While physical inactivity is one of the main contributors to obesity, it is a modifiable risk factor with exercise training as an established non-pharmacological treatment to prevent the onset of metabolic-related disorders, including obesity. Exposure to hypoxia via normobaric hypoxia (simulated altitude via reduced inspired oxygen fraction), termed hypoxic conditioning, in combination with exercise has been increasingly shown in the last decade to enhance blood glucose regulation and decrease the body mass index, providing a feasible strategy to treat obesity. However, there is no current consensus in the literature regarding the optimal combination of exercise variables such as the mode, duration, and intensity of exercise, as well as the level of hypoxia to maximize fat loss and overall body compositional changes with hypoxic conditioning. In this narrative review, we discuss the effects of such diverse exercise and hypoxic variables on the systematic and myocellular mechanisms, along with physiological responses, implicated in the development of obesity. These include markers of appetite regulation and inflammation, body conformational changes, and blood glucose regulation. As such, we consolidate findings from human studies to provide greater clarity for implementing hypoxic conditioning with exercise as a safe, practical, and effective treatment strategy for obesity.
Effects of exercise modality combined with moderate hypoxia on blood glucose regulation in adults with overweight

Tee CCL, Chong MC, Cooke MB, Rahmat N, Yeo WK, Camera DM

Front Physiol, 2024;15:1396108.
PMID: 38903909 DOI: 10.3389/fphys.2024.1396108

Purpose: This study aimed to investigate the combined effects of moderate hypoxia with three different exercise modes on glucose regulation in healthy overweight adults. Methods: Thirteen overweight males (age: 31 ± 4 years; body fat 26.3 ± 3.2%) completed three exercise trials in a randomized crossover design involving 60 min cycling exercise at 90% lactate threshold (LOW), sprint interval training (20 × 4 s all-out; SIT) and lower limb functional bodyweight exercises (8 sets of 4 × 20 s; FEX) under moderate hypoxia (FiO2 = 16.5%). Post-exercise oral glucose tolerance test (OGTT) was performed following each trial. Heart rate, oxygen saturation (SpO2), physical activity enjoyment scale (PACES), and perceptual measures were recorded during each exercise session. Venous blood was collected pre-, immediately post-, and 24 h post-exercise and analysed for plasma glucose and insulin, incremental area under curve (iAUC), and circulating microRNA expression (c-miRs-486-5p, -126-5p, and -21-5p). Interstitial glucose concentrations were measured using continuous glucose monitoring (CGM). Results: Post-exercise OGTT iAUC for plasma glucose and insulin concentration were lower in SIT and LOW vs. control (p < 0.05) while post-exercise interstitial glucose iAUC and c-miRs were not different between exercise modes. Heart rate was greater in SIT vs. LOW and FEX, and FEX vs. LOW (p < 0.05), SpO2 was lower in SIT, while PACES was not different between exercise modes. Perceptual measures were greater in SIT vs. LOW and FEX. Conclusion: Acute SIT and LOW under moderate hypoxia improved post-exercise plasma insulin compared to FEX exercises. Considering SIT was also time-efficient, well tolerated, and enjoyable for participants, this may be the preferred exercise modality for improving glucose regulation in adult males with overweight when combined with moderate hypoxia.
Physiological characteristics and performance of a world-record breaking tower runner

Loh TC, Tee CCL, Pok C, Girard O, Brickley G, James C

J Sports Sci, 2023 Mar;41(5):451-455.
PMID: 37286473 DOI: 10.1080/02640414.2023.2221957

This study reports the physiological and performance profiles of a world-class tower runner during a 6-week period surrounding a successful Guinness World Record (WR) attempt, and discusses the efficacy of a tower running specific field test. The world-ranked number 2 tower runner completed four exercise tests [laboratory treadmill assessment (3 weeks before the WR attempt), familiarisation to a specific incremental tower running field test (1 week before), tower running field test (1 week after), and tower running time trial (TT) (3 weeks after)] and the WR attempt within 6-week period. Peak oxygen consumption (VO2peak) during the laboratory test, field test, and TT were 73.3, 75.5 and 78.3 mL·kg-1·min-1, respectively. The VO2 corresponding to the second ventilatory threshold was 67.3 mL·kg-1·min-1 (89.1% of VO2peak), identified at stage 4 (tempo; 100 b·min-1), during the field test. The duration of the TT was 10 min 50 s, with an average VO2 of 71.7 mL·kg-1·min-1 (91.6% of VO2peak), HR of 171 b·min-1 (92% of peak HR), vertical speed of 0.47 m·s-1, and cadence was 117 steps·min-1. A world-class tower runner possesses a well-developed aerobic capacity. A specific, field-based test revealed greater VO2peak than a laboratory test, indicating a need for sport-specific testing procedures.
Influence of Running Velocity and Hypoxic Exposure on Vastus Lateralis Muscle Oxygenation

Yeap MW, Loh TC, Chong MC, Yeo WK, Girard O, Tee CCL

Int J Sports Physiol Perform, 2024 Sep 04.
PMID: 39231493 DOI: 10.1123/ijspp.2024-0083

PURPOSE: We investigated the effects of manipulating running velocity and hypoxic exposure on vastus lateralis muscle oxygenation levels during treadmill running.
METHODS: Eleven trained male distance runners performed 7 randomized runs at different velocities (8, 10, 12, 14, 16, 18, and 20 km·h-1), each lasting 45 seconds on an instrumented treadmill in normoxia (fraction of inspired oxygen [FiO2] = 20.9%), moderate hypoxia (FiO2 = 16.1%), high hypoxia (FiO2 = 14.1%), and severe hypoxia (FiO2 = 13.0%). Continuous assessment of Tissue Saturation Index (TSI) in the vastus lateralis muscle was conducted using near-infrared spectroscopy. Subsequently, changes in TSI (ΔTSI) data over the final 20 seconds of each run were compared between velocities and conditions.
RESULTS: There was a significant velocity × condition interaction for ΔTSI% (P < .001, ηp2=.19), with a smaller ΔTSI% decline in normoxia compared with high hypoxia and severe hypoxia at 8 km·h-1 (g = 1.30 and 1.91, respectively), 10 km·h-1 (g = 0.75 and 1.43, respectively), and 12 km·h-1 (g = 1.47 and 1.95, respectively) (pooled values for all conditions: P < .037). The ΔTSI% decline increased with each subsequent velocity increment from 8 km·h-1 (-9.2% [3.7%]) to 20 km·h-1 (-22.5% [4.1%]) irrespective of hypoxia severity (pooled values for all conditions: P < .048).
CONCLUSIONS: Running at slower velocities in conjunction with high and severe hypoxia reduces vastus lateralis muscle oxygenation levels. Muscle ΔTSI% proves to be a sensitive indicator, underscoring the potential use of near-infrared spectroscopy as a reference index of internal load during treadmill runs.