Evidence of long term durability of autologous tenocyte injection for treatment of chronic lateral epicondylitis

Abstract

Introduction: Initiated oral contraceptive (OC) use reduces peak aerobic capacity (VO2peak) in active women. However, whether training adaptations are influenced by OC use is yet to be explored. This study investigated whether OC use influenced VO2peak and peak power output (PPO) adaptations to 12 highintensity interval training (HIIT) sessions in recreationally-active women. Methods: Women taking an oral contraceptive (OC; n=25; age 25.2±5.2 years, BMI 22.6±2.1 kg/m2, VO2peak 36.1±5.6mL/kg/min; mean± SD) or experiencing natural menstrual cycles (MC; n=22; age 26.2±5.0 years, BMI 22.7±2.2 kg/m2, VO2peak 35.0±5.0mL/kg/min; mean± SD) completed a VO2peak familiarisation and hormone cycle mapping prior to beginning the study. Under stringently controlled test conditions, participants completed an incremental exercise test to volitional exhaustion to determine VO2peak and PPO prior to and following 12 sessions of HIIT (completed over four weeks). HIIT sessions consisted of 10 one-minute cycling intervals in a 1:2 work:rest ratio at 100–120% PPO. Paired t-tests were used to determine change from baseline. A two-way repeated measures ANOVA (with a main effect for training time×group) was used to determine whether an interaction occurred between training and group. The statistical significance level set at p 0.05). Following training, PPO increased in both groups (MC, 13.1%; p<0.001, and OC, 13.3%; p<0.001) with nodifferencebetweengroups (p=0.945). VO2peak increased followingHIIT (MC, 11.9%;p<0.001,OC, 7.6%;p<0.001),withMCshowing significantly greater improvement (p=0.028). Discussion: HIIT increased both PPO and VO2peak in recreationally active women; however OC users showed reduced improvements in VO2peak compared with MC women. OC use therefore appears to reduce physiological (VO2peak) adaptation to HIIT, however does not appear to detriment performance (PPO) outcomes. In conclusion, the data from this study provide a strong case for inclusion of ovarian hormone status control measures in female-specific research. Additionally, results encourage careful interpretation of VO2peak outcomes in female populations especially when investigating clinical relevance of VO2peak and associated health outcomes with training interventions. Practically, findings encourage careful consideration by active women regarding whether OC use may influence individual exercise goals. Further research should investigate potentialmechanisms responsible for this effect and whether performance and health benefits gained through HIIT are negatively impacted by OC use.