Theme1:  The effectiveness of different types of aerobic exercise in lowering blood pressure.  3.1.1 Water versus land exercise training

There are many different types of aerobic exercise or as it called cardio that can be a way of managing the blood pressure. Aquatic exercises are widely used as rehabilitation or preventive therapies specially for older people, as they enable mobilization and muscle strengthening for the lower limbs (Kutzner et al., 2017). In addition, it provides advantages for the elderly because of its lower risk of injury as a result of water buoyancy, and because it guards against joint degradation by reducing weight-bearing loads and reducing the joint load (Kutzner et al., 2017). Moreover, relating this to the study question. Through immersion, aquatic exercise stimulates physiological adjustments that can affect blood pressure and cardiac work, particularly by reducing sympathetic activity and redistributing blood volume from the lower body to the upper body (Reichert et al., 2018). It has been shown that after an acute exercise session, individuals can experience immediate or short-term benefits that last for up to 24 hours. As Gomes et al. (2020) study revealed that the post-exercise hypotension (PEH) for SBP and DBP last for 24 hours post aquatic-based training, which is longer than for land-based training. The post-exercise hypotensive response is considered a vital treatment factor for hypertension (HTN). Additionally, research conducted by Gomes et al. (2020) reveals that exercise in the water during the day lowered systolic blood pressure (SBP) and diastolic blood pressure (DBP) in elderly hypertensive individuals. Similarly, the research conducted by Reichert et al. (2020) showed that aerobic training under water reduced the systolic blood pressure(SBP). The individual blood pressure pretraining was at 130 mmHg, and post eight weeks, it decreased to 129 mmHg, and post 16 weeks, it reached to 124 mmHg. In comparison with pretraining measurements, SBP showed a significant reduction after eight weeks and 16 weeks of training. From pretraining to 16 weeks post training, SBP dropped by 6 mmHg. Likewise, this result is in agreement with Gomes et al. (2020), as the result display that under the water exercise group showed lower SBP and DBP than the land based exercise group. 

the study done by Gomes et al. (2020) confirms that the water training resulted in a more remarkable reduction of -10.58 mmHg than that to land  aerobic exercise -3.5 mmHg. This shows the effectiveness of the underwater workout compared to the land training. 

Gomes et al. (2020) stipulate that the group doing the aquatic exercise had a daytime reduction in BP of 1.0 mmHg in their SBD and 1.5 mmHg in their DBD. The reduction was, however, lower in the group doing the land-based exercises, where there was a reduction of 0.9 mmHg in the SBP and 0.9 mmHg in the DBP. The results showed no significant differences in the nighttime blood pressures. The post-exercise hypotension achieved following aquatic-based exercises was maintained up to 24th after exercise, while that land exercise-induced post-exercise hypotension was maintained to 12th-hour post-exercise. 

The BP measurements taken at the 24th hour showed a lower BP in groups that participated in the aquatic-based exercises than those involved in land-based exercises. Gomes et al. (2020) suggest that aquatic training exercises were more effective in lowering the daytime BP of elderly hypertensive patients. It also significantly lowered the resting SDP and DBP compared to individuals who participated in land-based exercises. Lastly, the blood pressure fell rapidly for individuals who participated in aquatic-based exercises, and the post-exercise hypotension lasted longer than for those who participated in the land-based exercises.

Therefore, the study's findings prove that aquatic-based exercises can lower the BP of elderly patients, given their effectiveness compared to land-based exercises. Reichert et al. (2018) further emphasize the need for aquatic training to reduce resting blood pressure for hypertensive patients. The study suggests that aquatic aerobic exercises help reduce the renin-angiotensin and sympathetic activities within the body and subsequently reduce the total peripheral vascular resistance and, eventually, the resting blood pressure. 

This was further confirmed in the study, where the intervention showed a progressive reduction in the participants' systolic blood pressure. This ranged from pre-training, after 8 weeks, and after 16 weeks of training as well. The BP values of the participants classified them as stage 1 hypertensive. This, however, changed since, after the 8 weeks of training, the BP values obtained had significantly reduced, and they were qualified for clarification as having normal blood pressure.

There are various forms of exercise in which individuals can participate and help reduce the blood pressure of hypertensive individuals. Some of these ex