Effects and experiences of exercise during pregnancy

Background: Recommendations regarding intensity, duration and type of exercise during pregnancy vary worldwide. Most research on exercise during pregnancy investigates the effects of aerobic exercise while only a few trials have studied the effects of resistance exercise. Obesity is a growing public health problem and little is known about obese pregnant women´s experiences of participating in a lifestyle intervention focusing on diet and physical activity. Specifically, in four studies, this thesis aims to: 1) describe experiences of exercise during pregnancy among women engaged in regular resistance training; 2) evaluate the health effects, in healthy pregnant women, of moderate to vigorous-intensity resistance exercise with free weights; 3) investigate and compare blood pressure (BP), heart rate (HR), body temperature and ratings of perceived exertion (RPE) during and after two single sessions of light to moderate continuous exercise, Nordic walking and resistance exercise, in healthy women in the second trimester of pregnancy; and 4) describe the experiences of women with obesity related to participating in a lifestyle intervention, and its experienced impact on health and lifestyle. Methods: A combination of quantitative and qualitative methods was used to elucidate different aspects of interest. Study I was assumed to complement studies II (a randomized controlled trial) and III (a cross over design) by adding a wider variety of viewpoints and experiences of resistance exercise as qualitative studies can. Study IV was considered to complement a range of quantitative studies evaluating the effects of lifestyles interventions in pregnancy. Results: Exercise was perceived to have a positive impact on body and mind and was thus described as generating both immediate and short-term health benefits. The women experienced that exercise led to a sense of control in pregnancy; problems related to pregnancy such as weight gain, poor posture, nausea, fatigue, headache, insomnia and back pain were perceived to be resolved and/or addressed. Performing resistance exercises generated an experience that their body was capable of many types of exercises, and they also found it valuable for acquiring good posture. The women considered that resistance training was a suitable type of exercise during pregnancy (Study I). The women’s functional status deteriorated during the intervention in both the intervention and control groups and pain increased. There were only significant differences between the groups for birthweight. Newborns delivered by women who underwent resistant exercise during pregnancy were significantly heavier than those born to control women; 3561 (±452) g versus 3251 (±437) g (p=0.02), a difference that disappeared when adjustment was made for gestational age (p=0.059). Both groups showed normal health related quality of life, blood pressure and perinatal data (Study II). During exercise, there was a significant increase in systolic BP and HR (p<.001). Diastolic BP increased, slightly more during aerobic exercise (p=.01) than resistance exercise (p=.03). Resistance exercise was perceived as more intense than aerobic exercise during 15 minutes (p=.02) and 30 minutes (p=.001) of exercise. After both types of exercise, BP quickly reverted to normal, although HR was still increased five minutes post-exercise (p=.001). There was a moderate but non-significant correlation between HR and RPE during 15 minutes of aerobic exercise, (rs=.43; p=.06), but the other correlations were weak (rs<0.2) and non-significant. Orally measured temperature decreased during aerobic exercise (p=.008) (Study III). The essence of the women’s experiences of participating in a lifestyle intervention during pregnancy was their expressed need for support to implement new habits, provided by midwives, partners, relatives and friends—as well as by obese pregnant women in the same situation. The midwives’ support was experienced as non-judgmental with a balanced outlook on weight. The essential structure of participation can be described with the following constituents: ‘‘pregnancy encourages change’’; ‘‘non-judgmental support’’; ‘‘from bad habits to conscious choices’’ and; ‘‘barriers to change’’ (Study IV). Conclusion: Among healthy women who exercise regularly, from walks to moderate-to-strenuous exercise, regular moderate intensity resistance exercise appears to be appropriate during the second trimester of pregnancy. Pregnant women who perform this type of exercise considered it as suitable. Aerobic and resistance exercise corresponding to 13¬–14 on the Borg RPE-scale seems to be safe with regard to blood pressure and heart rate responses in second trimester healthy pregnancies. In order to implement new habits, participants of a lifestyle intervention express a need for support, given with a non-judgmental attitude and a balanced outlook on weight. For controlling gestational weight gain, lifestyle interventions focusing on healthy eating patterns are probably of major importance

Fluorinated cyclothiaphosphazenes:Synthesis, structure and reactivity

Reaction of chlorocyclothiaphosphazenes NPCl2(NSOX)(2) (X = Cl, Ph) and (NPCl2)(2)NSOX (X = Cl, F, Ph) with KSO2F in bulk leads to fluorination at the phosphorus centers. The substitution reaction follows a geminal pattern. Reactions of trans-NPF2(NSOPh)(2) with Grignard reagents RMgX (R = Me, (t)Bu) show substitution of fluorine by alkyl groups to be a slow process. The more reactive PhMgBr gives an acceptable reaction rate and good yields. Organolithium reagents offer organo-substituted cyclothiaphosphazenes in low to moderate yields, depending on the reagent used. Crystals of cis-NPF2(NSOPh)(2) are monoclinic, space group P2(1)/n, with a = 13.665(7) Angstrom, b = 10.676(1) Angstrom, c = 9.897(3) Angstrom, beta = 90.55(3)degrees, V = 1443.8(9) Angstrom(3), and Z = 4. The final R and wR values are 0.034 and 0.043, respectively. The PN and SN bond lengths vary from 1.571(2) to 1.590(2) Angstrom

Polymerization of Organo-Substituted Silanes by Hydroslylation

Polymerization of unsaturated organo-substituted silanes by catalytic hydrosilylation leads to both polymeric and cyclic carbosilanes

Preparation of urethane and urea derivatives of (NPCl2)3: Crystal structure of a spirocyclic phosphazene with a phosphacyanuric loop

Reactions of (NPCl2)3 with NaNCO in the presence of aliphatic alcohols have been investigated. Using an equimolar amount of NaNCO in refluxing acetonitrile, high yields of mono(urethane) derivatives N3P3Cl5(NHCO2R) were obtained. Disubstitution is mainly non-geminal. Reactions of (NPCl2)3 with AgNCO and methanol in acetonitrile follow a quite different pattern and lead to the formation of three products with basically geminal structures, e.g. gem-N3P3Cl4(OR)(NHCO2R), gem-N3P3Cl4(NH-CO2R)2, and a spiro derivative (NPCl2)2NP[N(CO2R)C(O)NHC(CH3)N]. The crystal structure of the last compound (R = CH3) has been determined. The difference between the reaction pathways observed for NaNCO and AgNCO is discussed in terms of S(N)2 and S(N)1 mechanisms, respectively. An improved synthesis of (NPCl2)2NP(NH2)(NCO) and its reactions with alcohols and amines are described

Polymerization of Propene with Modified Constrained Geometry Complexes. Double-Bond Isomerization in Pendant Alkenyl Groups Attached to Cyclopentadienyl Ligands

Polymerization of propene with dimethylsilylene-bridged (amidocyclopentadienyl)dichlorotitanium(IV) complexes [TiCl2{η5-1-(t-BuSiMe2N-κN)-2,3,4-Me3-5-R-C5}], where R = Me (1), H (2), Ph (3), 4-fluorophenyl (4), but-2-en-2-yl (5), and butyl (6), combined with excess methylaluminoxane revealed a moderate effect of the substituent R on the catalyst activity and the molecular weight of polypropene. The asymmetric substitution in the position adjacent to the bridging carbon atom resulted in polymer yields decreasing in the order 1 > 6 > 3 ≈ 5 > 4 > 2 while polymers with the molecular weights (Mw) close to 2.5 × 10e5 for 1, 3, and 4, 1.5 × 10e5 for 5 and 6, and 7.5 × 10e4 for 2 were obtained. The 13C NMR analysis of the polymers has shown that atactic polypropene is slightly enriched with syndiotactic triads for all the catalysts. Investigation of the crystal structure of 5 by X-ray crystallography revealed that the double bond in but-3-en-2-yl had shifted to an internal position to give the isomeric, but-2-en-2-yl-substituted complex. Likewise, the spectroscopic data for complex 7 prepared from the ligand containing but-3-en-1-yl substituent, indicate the absence of terminal double bond.

Silicon-Containing Polymers Derived from Mono and Disubstituted Cyclophosphazenes

Two classes of silicon-containing polymers are described, one in which phosphazene rings are part of the polymer backbone, the other where phosphazene rings are present as pendant groups. X-ray structures of some monomeric precursors and reaction products are shown