A Comparison of V̇O 2 , and Muscle and Prefrontal Cortex Tissue Oxygen Extraction between Short and Long-term Aerobically Trained Men Aged 40 - 60 Years.

This study was designed to compare systemic O2 utilization (V̇O2), and changes in tissue O2 extraction [deoxyhemoglobin (ΔHHb)] in the vastus lateralis (VL), gastrocnemius (GAST) and pre-frontal cortex (PFC) tissue; between aerobically short-term trained (STT) and long-term trained (LTT) older men (40 - 60 yr) who were matched for current training load. On separate occasions, 14 STT and 14 LTT participants completed ramp incremental (RI) and square-wave constant load (SWCL) tests on a cycle ergometer. In LTT compared to STT; (i) V̇O2 was higher during the RI (p > 0.001) and SWCL (p > 0.001) tests, (ii) ΔHHb in the GAST was greater in SWCL (p = 0.011); and (iii) ΔHHb in the PFC was greater at 90% GET during SWCL (p = 0.011). The additional years of training in LTT compared to STT (LTT 17.50yr ± 6.94yr vs STT 1.68yr ± 0.31yr) were associated with higher V̇O2peak, and sub-GET V̇O2, and ΔHHb in the GAST and PFC at sub-GET exercise, despite there being no difference in current training volume.

The Effect of Short- and Long-Term Aerobic Training Years on Systemic O2 Utilization, and Muscle and Prefrontal Cortex Tissue Oxygen Extraction in Young Women.

Buzza, G, Lovell, GP, Askew, CD, and Solomon, C. The effect of short- and long-term aerobic training years on systemic O2 utilization, and muscle and prefrontal cortex tissue oxygen extraction in young women. J Strength Cond Res 33(8): 2128-2137, 2019-This study aimed to determine if systemic O2 utilization (VO2) and tissue oxygen extraction (deoxyhemoglobin [HHb]) in the vastus lateralis (VL), gastrocnemius (GAST), and prefrontal cortex were different during exercise between short-term trained (STT, 6-24 months) and long-term trained (LTT, >5 years) young women while controlling for current training load. Thirteen STT and 13 LTT participants completed ramp incremental (RI) and square-wave constant load (SWCL) tests on a cycle ergometer. In LTT compared with STT: (a) VO2 was higher during the RI (p = 0.024) and SWCL (p = 0.001) tests; (b) HHb in the VL (p = 0.044) and GAST (p = 0.027) was higher in the RI test; and (c) there were significant group × intensity interactions for VO2 in the SWCL test. The additional years of aerobic training in LTT compared with STT (LTT 7.1 ± 1.9 vs. STT 1.5 ± 0.4 years) resulted in higher VO2 and HHb in the VL and GAST. These results indicate that in young women, independent of current training load, systemic VO2 and peripheral muscle O2 extraction during exercise continues to increase beyond 24 months of aerobic training.

The Effect of Short and Long Term Endurance Training on Systemic, and Muscle and Prefrontal Cortex Tissue Oxygen Utilisation in 40 - 60 Year Old Women.

PURPOSE: Aerobic endurance training (ET) increases systemic and peripheral oxygen utilisation over time, the adaptation pattern not being linear. However, the timing and mechanisms of changes in oxygen utilisation, associated with training beyond one year are not known. This study tested the hypothesis that in women aged 40-60 years performing the same current training load; systemic O2 utilisation (VO2) and tissue deoxyhaemoglobin (HHb) in the Vastus Lateralis (VL) and Gastrocnemius (GAST) would be higher in long term trained (LTT; > 5 yr) compared to a short term trained (STT; 6-24 months) participants during ramp incremental (RI) cycling, but similar during square-wave constant load (SWCL) cycling performed at the same relative intensity (below ventilatory turn point [VTP]); and that pre-frontal cortex (PFC) HHb would be similar between participant groups in both exercise conditions. METHODS: Thirteen STT and 13 LTT participants performed RI and SWCL conditions on separate days. VO2, and VL, GAST, and PFC HHb were measured simultaneously. RESULTS: VO2peak was higher in LTT compared to STT, and VO2 was higher in LTT at each relative intensities of 25%, 80% and 90% of VTP in SWCL. HHb in the VL was significantly higher in LTT compared to STT at peak exercise (4.54 ± 3.82 vs 1.55 ± 2.33 µM), and at 25% (0.99 ± 1.43 vs 0.04 ± 0.96 µM), 80% (3.19 ± 2.93 vs 1.14 ± 1.82 µM) and 90% (4.62 ± 3.12 vs 2.07 ± 2.49 µM) of VTP in SWCL. CONCLUSIONS: The additional (12.9 ± 9.3) years of ET in LTT, resulted in higher VO2, and HHb in the VL at peak exercise, and sub-VTP exercise. These results indicate that in women 40-60 years old, systemic and muscle O2 utilisation continues to improve with ET beyond two years.

Examining the use of evidence-based and social media supported tools in freely accessible physical activity intervention websites.

BACKGROUND: It has been shown that physical activity is more likely to increase if web-based interventions apply evidence-based components (e.g. self-monitoring) and incorporate interactive social media applications (e.g. social networking), but it is unclear to what extent these are being utilized in the publicly available web-based physical activity interventions. The purpose of this study was to evaluate whether freely accessible websites delivering physical activity interventions use evidence-based behavior change techniques and provide social media applications. METHODS: In 2013, a systematic search strategy examined 750 websites. Data was extracted on a wide range of variables (e.g. self-monitoring, goal setting, and social media applications). To evaluate website quality a new tool, comprising three sub-scores (Behavioral Components, Interactivity and User Generated Content), was developed to assess implementation of behavior change techniques and social media applications. An overall website quality scored was obtained by summing the three sub-scores. RESULTS: Forty-six publicly available websites were included in the study. The use of self-monitoring (54.3%), goal setting (41.3%) and provision of feedback (46%) was relatively low given the amount of evidence supporting these features. Whereas the presence of features allowing users to generate content (73.9%), and social media components (Facebook (65.2%), Twitter (47.8%), YouTube (48.7%), smartphone applications (34.8%)) was relatively high considering their innovative and untested nature. Nearly all websites applied some behavioral and social media applications. The average Behavioral Components score was 3.45 (±2.53) out of 10. The average Interactivity score was 3.57 (±2.16) out of 10. The average User Generated Content Score was 4.02 (±2.77) out of 10. The average overall website quality score was 11.04 (±6.92) out of 30. Four websites (8.7%) were classified as high quality, 12 websites (26.1%) were classified as moderate quality, and 30 websites (65.2%) were classified as low quality. CONCLUSIONS: Despite large developments in Internet technology and growth in the knowledge of how to develop more effective web-based interventions, overall website quality was low and the majority of freely available physical activity websites lack the components associated with behavior change. However, the results show that website quality can be improved by taking a number of simple steps, and the presence of social media applications in most websites is encouraging.