BACKGROUND: There are alterations in strength in relation to menstrual cycle phase but little data attributing these responses to female sex hormone levels using a pseudo-menstrual cycle group as control. OBJECTIVE: Examining the effects of menstrual cycle phase on the development of peak torque across a range of isokinetic speeds. METHOD: 17 well trained females, 11 formed the non-oral contraceptive group (n-OC) (age 20.7 ± 1.4 yrs, mass 59.2 ± 6.9 kg, height 166.8 ± 7.1 cm) and 6 the oral contraceptive control group (OC) (age 20.3 ± 0.5 yrs, mass 60.5 ± 4.2 kg, height 164.8 ± 4.8 cm). Concentric strength of the knee flexors and extensors (60-240 • /s) was assessed, corresponding to menstruation (MEN), mid-follicular (mFOL), mid-luteal (mLUT) and pre-menstrual (pMEN). RESULTS: For n-OC significant decreases in peak torque production of the extensors at 120 • /s (P = 0.0207) (MEN) and of the flexors at 60 • /s (P = 0.0116) (MEN) and 120 • /s (P = 0.0282) (MEN) were observed compared to pMEN. No significant differences were observed across any menstrual cycle phase and peak torque for the OC group (p > 0.05). Significant positive correlations were observed (mLUT) between peak torque and oestrogen at 60 • /s (P = 0.040) and 120 • /s (P = 0.031). CONCLUSIONS: There are significant fluctuations in peak torque of the knee extensors in response to phases of the menstrual cycle associated with variances in the female sex hormones. The findings have implications for the planning of strength training in female athletes.
PurposeThe aim of this study was to examine the physical and training characteristics of recreational marathon runners within finish time bandings (2.5–3 h, 3–3.5 h, 3.5–4 h, 4–4.5 h and >4.5 h).Materials and methodsA total of 97 recreational marathon runners (age 42.4 ± 9.9 years; mass 69.2 ± 11.3 kg; stature 172.8 ± 9.1 cm), with a marathon finish time of 229.1 ± 48.7 min, of whom n = 34 were female and n = 63 were male, completed an incremental treadmill test for the determination of lactate threshold (LT1), lactate turn point (LT2) and running economy (RE). Following a 7-min recovery, they completed a test to volitional exhaustion starting at LT2 for the assessment of trueV˙normalO2max. In addition, all participants completed a questionnaire gathering information on their current training regimes exploring weekly distances, training frequencies, types of sessions, longest run in a week, with estimations of training speed, and load and volume derived from these data.ResultsTraining frequency was shown to be significantly greater for the 2.5–3 h group compared to the 3.5–4 h runners (P < 0.001) and >4.5 h group (P = 0.004), while distance per session (km·session−1) was significantly greater for the 2.5–3 h group (16.1 ± 4.2) compared to the 3.5–4 h group (15.5 ± 5.2; P = 0.01) and >4.5 h group (10.3 ± 2.6; P = 0.001). Race speed correlated with LT1 (r = 0.791), LT2 (r = 0.721) and distance per session (r = 0.563).ConclusionThe data highlight profound differences for key components of marathon running (trueV˙normalO2max, LT1, LT2, RE and % trueV˙normalO2max) within a group of recreational runners with the discriminating training variables being training frequency and the absolute training speed.
The purpose of this study was to examine the effect of menstrual cycle phase on maximal oxygen uptake (V˙O2max) and associated cardiodynamic responses. A total of 16 active females volunteered of which n = 10 formed the non-oral contraceptive pill group (n-OCP), displaying a regular menstrual cycle of 28·4 ± 2·2 days (age 20·6 ± 1·6 years, height 169·9 ± 6·4 cm, mass 68·7 ± 7·9 kg) and n = 6 formed the oral contraceptive pill group (OCP) (monophasic pill) (age 21·7 years ± 2·16, height 168·1 cm ± 6·8 cm, mass 61·6 ± 6·8 kg). Each completed four incremental exercise tests for determination of V˙O2max, cardiac output, stroke volume and heart rate. Each test was completed according to the phases of the menstrual cycle as determined through salivary analysis of 17-β oestrodiol and progesterone. Non-significant differences were observed for V˙O2max across phases and between groups (P>0·05) with additional non-significant differences for Q˙max, HR and SV between groups. For ∆ V˙O2 during the final 60 s of the V˙O2max trial, significant differences were observed between OCP and n-OCP (P<0·05) with OCP showing zero V˙O2 plateaus in three pseudo-phases. Significant difference observed for a-vO n-OCP between premenstruation and menstruation at 30-100% V˙O2max (P<0·05). Data suggest that the V˙O2 -plateau is effected by monophasic oral contraceptive pill, furthermore these data imply that V˙O2max test outcome is independent of menstrual cycle phase but caution should be applied when evaluating maximal oxygen uptake in females who are administered a monophasic oral contraceptive pill.
Children of South Asian ethnicity residing in England have low levels of physical activity. Limited literature exists on correlates, barriers, and facilitators to activity in South Asian children. The aim of this study was to fill this gap in the literature. Interviews were conducted with 10 parents of South Asian ethnicity residing in the UK. Interviews covered a description of the family setup, participants' opinions of physical activity including barriers and facilitators and their children's participation, as well as approaches to general parenting, and how children spend their free time. Data were analysed using thematic analysis. Key themes identified included (i) restraints on parents' and children's time to be physically active; (ii) the role of the family in children's physical activity participation; (iii) situational barriers to physical activity; (iv) physical activity not a priority; (v) opportunities to be active; and (vi) perception of activity level and health. A number of key barriers to South Asian children's participation in physical activity were identified, including (i) restraints on parents and children's time; (ii) parents providing limited support for physical activity; and (iii) physical activity having a low priority. A number of facilitators were also identified (i) play; (ii) school-time; and (iii) extra-curricular clubs. In this sample of South Asian parents residing in the UK several socio-cultural barriers and facilitators of their children's physical activity have been identified. The study provides preliminary data for a larger study to ascertain if such barriers and facilitators are representative of the wider South Asian community, so that recommendations for intervention and policies can be made.
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