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Dont forget that cyclists are not the only group of athletes who can benefit from bicarbonate supplementation. Strength trainees who spend hours in the gym and train at high intensities will also benefit!

I know that most of you are into resistance not endurance training. So, before I even get into the discussion of the experimental procedures and the results of the latest study from the Institute of Sports and Preventive Medicine at the Saarland University in Saarbrücken, Germany, I would like to point you to an older SuppVersity article which indicates that bicarbonate supplementation is able to Up Your Squat (+27%) & Bench Press (+6%) Within 60 Min" (read more).

Now that youve hopefully put away your prejudices against "that endurance supplement", lets get to the previously mentioned study by Florian Egger, Tim Meyer, Ulf Such, and Anne Hecksteden (thanks to Conrad P. Earnest for bringing this to my attention).
To investigate the effects of BICA supplementation on performance during prolonged, high-intensity cycling to exhaustion in well-trained athletes, the scientists from the Saarland University recruited 6 male and 5 female "well-trained" cyclists (mean ± SD: age 24±8 y, BMI 21.3±1.7, VO2peak 67.3±9.8 ml/kg/min - the VO2peak value tells you that they were fit ;-).

In a double-blind, randomized cross-over design, the subjects underwent two stepwise incremental exercise tests and two constant load tests (with two phases) on an electrically braked cycle ergometer (Excalibur Sport, Lode, Groningen, The Netherlands).

Figure 1: Schematic representation of the general design.Time interval between tests is specified in days (d). Data are presented as means ± standard deviation respectively, with minimum (min) and maximum (max) values (Egger. 2014).

As the overview of the study design in Figure 1 tells you, each test type was completed twice. Once after the ingestion of 0.3 g/kg sodium bicarbonate (yes, thats roughly 24g for someone who weighs 80g and should not be consumed too fast, because otherwise it may trigger diarrhea) or a placebo supplement in form of 4 g sodium chloride that was chosen to make sure that any benefits that were observed were due to the natrium, not the bicarbonate content of sodium bicarbonate.
Both the plain salt and the sodium bicarbonate were solved in 0.7 l water. The outcome measures were simple: Only if the subjects were able to pedal significantly longer until they were exhausted in the standardized constant load test, sodium bicarbonate could be considered to have practically relevant performance enhancing effects (maximum performance in the stepwise incremental exercise test, i.e. maximal workload and VO2peak were used as secondary outcomes).

Figure 2: Blood lactate (BLa) concentrations after ingestion (post drink) and during constant load tests (mean ± SD) for the BICA and placebo trials (Egger. 2014)

The other parameters the scientists measured, i.e. the blood lactate [BLa], pH, and bicarbonate concentration, were merely used determine the mechanisms for the potential improvements in exercise performance.

Speaking of auxiliary measures, if you take a look at Figure 2 you will see that the blood pH dropped significantly right after the ingestion of the bicarbonate supplement and remained "low" throughout the trial and afterwards. An observation that does not come unexpected. Previous trials have after all shown that its the ability of bicarbonate to blunt the high-intensity exercise related perturbations in both blood and muscle acid-base that keeps the maximal work rate up and leads to performance increases compared to placebo supplements.
These performance decrements are caused by the accumulation of hydrogen ions (H+) in the myoplasm and their detrimental effects on myofilament interaction, glycolytic flux and sarcoplasmatic reticulum function. As Egger et al. point out

"[t]he ability of the body to prevent or delay these force limiting processes is determined by the capacity of its intrinsic buffering systems, which counteract the accumulation of H+ both inside and outside the cell," (Egger. 2014)

which explains why the benefits of both beta alanine (which increases the intra-cellular buffering capacity) and bicarbonate are most pronounced in athletes competing in high intensity sports.

Figure 3: Time to exhaustion and maximal workload (total) and maximal workload at the individual anaerobic threshold (IAT) during the bicarbonate and placebo trials (Egger. 2014).

Apropos ergogenic effects: I already gave it away in the headline. The consumption of the bicarbonate supplement lead to immediate increases in the time to exhaustion with 49.5 ±11.5 min being the maximum in the bicarbonate and 45.0±9.5 min being the maximum in the placebo condition.

The maximal workload in the stepwise incremental tests (BICA: 341±66 W; placebo: 339±67 W) and workload at IAT (BICA: 234±5.5 W; placebo 233±5.7 W), on the other hand, did not differ significantly.
References:

• Egger F, Meyer T, Such U, Hecksteden A. "Effects of Sodium Bicarbonate on High-Intensity Endurance Performance in Cyclists: A Double-Blind, Randomized Cross-Over Trial". PLoS ONE 9.12 (2014): e114729.
• Hobson, Ruth M., et al. "Effects of ?-alanine supplementation on exercise performance: a meta-analysis." Amino acids 43.1 (2012): 25-37.

Resistance training alone wont make up for a sloppy diet - no matter if you do it before or after meals.

I am not sure how feasible this is going to be for you, but if you are a type II diabetic or anyone concerned about the potential detrimental health effects of the rise in glucose and triglycerides after a meal, working out 45 minutes after dinner is the way to go.

Abnormally elevated postprandial glucose and triacylglycerol (TAG) concentrations are strong risk factors for cardiovascular disease (CVD) in patients with type-2 diabetes. Therefore, scientists expect that interventions that reduce postprandial glucose and TAG concentrations should lower the risk of CVD (Krook. 2003; OGorman. 2008).
Previous studies have shown that acute exercise typically lowers postprandial glucose and TAG concentrations (Tobin. 2008) in patients with type-2 diabetes, but as Timothy D. Heden et al. point out, there is considerable heterogeneity in the responses with some individuals not experiencing beneficial changes in these risk factors (Gill. 2007; van Dijk. 2012).

"One potential explanation why some patients with type-2 diabetes do not have beneficial changes in postprandial glucose and TAG with acute exercise is because of the timing of the acute exercise session relative to meal consumption. Limited evidence suggests that the timing of aerobic exercise around a meal may be important and might explain why some individuals are exercise “insensitive” or “non responders”." (Heden. 2014) 

The only study to directly compare the effect of pre-meal and post-meal aerobic exercise on postprandial glucose concentrations in patients with type-2 diabetes showed that post-dinner, but not pre-dinner walking, lowered postprandial glucose concentrations (Colberg. 2009).

Figure 1: Previous studies indicate that aerobic workouts after meals have more beneficial effects on the potentially unhealthy increases in glucose or triglycerides (Collberg. 2009)

Although no study has directly examined the effect of exercise timing on postprandial TAG in patients with type-2 diabetes, there is evidence that exercise performed the day prior to a high fat meal has no effect on postprandial TAG responses (Dalgaard. 2004; Gill. 2007), while post-breakfast aerobic exercise reduced the postprandial TAG response (Tobin. 2008). Taken together, it appears that aerobic exercise may have its most powerful effect to lower postprandial glucose and TAG responses when performed after a meal, possibly because of slowed gastric emptying and/or greater skeletal muscle glucose and TAG uptake and utilization at this time.

The question that remained was: Is the same true for resistance training?

Since resistance exercise (RE) has a more pronounced long(er)-lasting effect on ones metabolism than aerobic training, the researchers from the University of Missouri tested the hypothesis that post-dinner RE, compared to pre-dinner RE, would in fact be more effective at improving two clinically important postprandial risk factors (glucose and 109 TAG) for CVD at a time of day when they are typically highest in obese patients with type-2 diabetes.

The standardized test workout consisted of the following exercises (in this order): leg press, seated calf raises, seated chest flyes, seated back flyes, back extensions, shoulder raises, leg curls, and abdominal crunches. All exercises were performed for three sets (1-2 min rest between sets) of 10-repetitions for each RE. During this session, the first set for each exercise was a warm-up set and the weight used was 50% of the participants 10-RM. After the warm-up set, the weight for the next two sets was the participants previously determined 10-RM.

Figure 2: Postrandial lipid response in the obese type II diabetics (Heden. 2014)

As you can see in Figure 2 the scientists suspicion was right, the postprandial workout (M-RE) had significantly more pronounced beneficial effects on the lipid metabolism of the type II diabetic subjects who consumed a standardized breakfasts (English muffin, cheddar cheese, one large egg, ham, hash brown, ketchup, and apple or orange juice) lunch (white bread, ham, mayonnaise, cheddar cheese, a granola bar, and apple or orange juice) and dinner meals (spaghetti noodles, spaghetti sauce with beef added, garlic bread, a lemon lime flavored soda, and 1.5 g of acetaminophen (to assess gastric emptying)) containing ~50% carbohydrate, 35% fat, and 15% protein.

Similar effects were observed for the insulin and glucose responses (see Figure 3) which were significantly improved and should thus complement the beneficial effects of the reduced triglyceride and very low density lipoprotein (VLDL) levels.
References:

• Colberg, Sheri R., et al. "Postprandial walking is better for lowering the glycemic effect of dinner than pre-dinner exercise in type 2 diabetic individuals." Journal of the American Medical Directors Association 10.6 (2009): 394-397. 
• Dalgaard, Marian, Claus Thomsen, and Kjeld Hermansen. "Effects of one single bout of low-intensity exercise on postprandial lipaemia in type 2 diabetic men." British Journal of Nutrition 92.03 (2004): 469-476.
• Gill, Jason MR, et al. "Effect of prior moderate exercise on postprandial metabolism in men with type 2 diabetes: heterogeneity of responses." Atherosclerosis 194.1 (2007): 134-143.
• Heden, Timothy D., et al. "Post-dinner resistance exercise improves postprandial risk factors more effectively than pre-dinner resistance exercise in patients with type 2 diabetes."
  Journal of Applied Physiology (2014). Ahead of print.
• Krook, Anna, et al. "Reduction of risk factors following lifestyle modification programme in subjects with type 2 (non?insulin dependent) diabetes mellitus." Clinical physiology and functional imaging 23.1 (2003): 21-30.
• OGorman, Donal J., and Anna Krook. "Exercise and the treatment of diabetes and obesity." Endocrinology and metabolism clinics of North America 37.4 (2008): 887-903.
• Tobin, L. W. L., Bente Kiens, and Henrik Galbo. "The effect of exercise on postprandial lipidemia in type 2 diabetic patients." European journal of applied physiology 102.3 (2008): 361-370.
• van Dijk, Jan-Willem, et al. "Exercise and 24-h glycemic control: equal effects for all type 2 diabetic patients?." Medicine and science in sports and exercise (2012).